Now it is lightweight ESL plugin that will not take space in your load order.

To use classes, just activate a standing stone of your choice, you will get a class connected to this stone.
Technically speaking, you are not forbidden to mix classes with other standing stones by clicking "no" when receiving a new standing stone.
But I created them to use with the respective standing stone in mind.

It does not require script extender or any other mod.
It is safe to install mid-play, if the mods you are using are not changing the activators list for Standing Stones. 
It is lightweight mod.


To Each Its Own. Class Additions To Standing Stones.

I always wanted to create a mod for my favourite Skyrim world, but every mod I needed was already created.
Except this one. I don't like standing stone overhauls, sure, every one of them is adding something new, but.
The problem is that they always remove the previous standing stone effect for the sake of "balance".
When I am looking for a standing stone overhaul, it is because I want the other standing stones to be as powerful as Lord!
I don't like the idea of nerfing something for the sake of nerfing or removing vanilla game features.

Welcome to the idea of class additions to the standing stones.

Is it considered a standing stone overhaul? The idea behind it was to divide these additions from standing stone blessings. And any other mod that is not adding new scripts to the doomStone activators is compatible.
It is my first mod, but I assure you will be surprised by the new play styles it brings.

As I said, the mod does not change any standing stone's powers or abilities, just adds new.
When you empower a weak standing stone with a strong class addition and a weak class with a strong standing stone, you get unique variants to choose from.

For example, Tower Stone can be useless, but with an addition of Witchhunter class it is a game breaker.
As well as Rebel class that breaks armor/stance defense is not so strong considering that not many characters in Skyrim even have a good armor to reduce your damage.
But Rebel empowered with Atronach Stone is a beast that can fight both armored orcs and nasty fire nukers.

"It is OP"

Not all combinations are powerful as hell, for example From-The-Shadows were created to make Shadow Stone a good choice if you need to complete just one sneaky quest and return back to your dragon slayer chores.
Classes are meant to be OP to the point of making every combination both switchable mid-game and hard to choose from.
You just play every till you find the favourite or two.

Combinations

Empowered means I consider a class weaker than a standing stone. Empowers means I consider standing stone weaker than a class.

Classes

Scholar Class empowers Apprentice Standing Stone

These casters study to learn and wield magic, usually taking years, leaving their bodies squishy and out of shape.
They are not inherent gift magicians, they initially bad at magic, but dedicated their life to study it.

This is why I choose to connect this class with an Apprentice Standing Stone that brings magical vulnerability.

Class abilities:
Dedication
The scholar has a superior dedication to study and can force himself to regenerate some magic <at will>. 
This lesser power lasts for <10> seconds. 

Overcharge
You are overcharged with magic! Maybe it is not so good for your health, but it gives you a cloak of electrical charge.
Damages near enemies at <5> damage per second that ignores any resistance and can't be absorbed or reflected.


Rebel Class empowered by Atronach Standing Stone

Rebel have an expert sense of guerilla warfare and survival tactics, he likes fighting dirty and can break through a weak spot in any armor or castle.
Rebels are against any authority, particularly in counterpart to the Knights/Guards/Paladins who represent the nobility and law.
And their skill to destroy armored foes demonstrates it.

Rebel is not a magical type, and is not protected from magical attacks, it is his weakness. 
This is why I decided to empower him with an Atronarch Stone.

Class abilities:
Find Weak Spot
Rebel can study enemies and figure out their weak spot in armor or stance. 
Use <at will> to ignore target enemy armor and stance for <10> seconds.

Teracte Grande
Creates an explosion with maximum fire damage of 30.

Agent Class empowered by Lady Standing Stone

Agents are operatives skilled in deception and avoidance, trained in self-defense and the use of deadly force. Self-reliant and independent, agents devote themselves to personal goals, or to various patrons or causes.
They are masters of the martial arts. It is an ultimate class to be alive while using no armor, weapons or magic.

You're disguised as an ordinary citizen or whoever you want.
But when the time comes, you can use your bare hands to bring damage and evade attacks.
Lady's grace and power is best suited to this class, IMHO.

Class abilities:
Martial Art
You are a trained martial artist with additional <40> unarmed damage.

Self-Defence
You can evade any attacks for <5> seconds <at will>.
This ability shines with lady's power to regenerate health and stamina more quickly.


Veteran Class empowered by Lord Standing Stone

A Veteran knows that war brings bloodshed and is not very eager to fight.
He is disciplined to give only effective strikes and tends to outrun others. 

He stays calm even during power attacks and saves fatigue.
I liked the idea to empower him with a Lord Stone.
He has experience of using different kinds of armor and weapons so bonus armor points and little magic resist makes perfect sense.
Also soldier is a lawful and authority respecting character and Lord is a good fit to it.

Class ability:
Power attacks cost no stamina.


Generalist Class empowers Mage Standing Stone

A Magician who does not specialize in one tradition and studies the magic of various types.
Knows enough to see the full picture and combine spell powers from different schools.
Of all the kinds of Magician, they tend to be the most open minded.

A typical Gendalf-style wizard with a vast knowledge of magical arts who use spells very effectively and smart.
The idea behind a generalist is a similar to a Veteran warrior. He uses every spell for a cheaper mana charge.

Class abilities:
Spells from any magical school have a half cost.


Summoner Class empowered by Ritual Standing Stone

The Magician who makes a pact with some magical creature or spirit. He then can summon the entity to them to do its bidding. Usually supplemented with some magic of another type. If the summoned entity sticks around for a while to assist the summoner.

I wanted to make it unique in the way that your mage can make a pact with a magical creature of your choice and call it for help whenever they need.
The best way to do it technically was to give 1 additional summon slot that should not conflict or override your conjuration perks, even if you use perk overhauls.
And since the <entity of your choice> can be summoned any time conjuration spells cost nothing. 
Also, your <friend/pet/whatever> can aid you in many ways. For example bring undead to fight for you once a day thanks to Ritual Stone ability.

Class abilities:
Warlock Pact
The Magician makes a pact with a summonable creature of your choice <1 additional slot>.
He can summon it at any time <conjuration spells are free>.

Ask For Aid
You can ask a creature you made a pact with for an aid. Creature then can restore your <15> health, <15> magic and <15> stamina.

Storm Chaser Class empowers Serpent Standing Stone

Firstly, let us all admit it just sounds cool. You will be sent to a Serpent Stone as a part of joining Stormcloaks quest if you do.
And applying the Storm Chaser class to this Standing Stone makes perfect sense to me.
Even though in most myths, snakes are natural enemies of lightning.
I would apply it to a Standing Stone that makes my character weaker, but I just did not find one.
In near every standing stone discussion, Serpent considered as weak, so that's it.

Storm chaser is descended from a Storm itself!
He strikes like a thunder and can utilize a powerful lightning spell that uses environmental electricity for a decreased cost.

I name it as the best end game class.

Class abilities:
Thunder Strike
Power attacks are 4 times more powerful.
85% of electrical resistance. (maximum player can get)

Thunder Fist
You use natural electricity to decrease the cost of a spell.
Actually, it is just a thunderbolt with basic damage of 480 and basic cost of 800. Which is extremely cheap.
But not that cheap to use before the late game.


From-The-Shadows Class empowers Shadow Standing Stone

Class created exclusively for Shadow stone. Consider it as an elite Shadowscale class.
Sometimes you see a nice quest mod you want to explore, but quest awards you for being sneaky or open new additional content when you're stealthy.
More of it, most of us Skyrim players tend to create sneaky archers just to be in some guild for a while or get some enchanting gear.
Not anymore! Sneak better! Be muffled! Don't raise illusion because quiet casting is included! Make stronger sneak attacks!

That's it, just use this class, make that damn quest and return back to your dragon slayer chores.

Class abilities:
Stronger sneak attacks, quiet casting, muffled, better sneak, stronger poison creation.


Treasure Hunter Class empowered by Steed Standing Stone

Treasure hunters are opportunists and glory seekers with a penchant for adventuring.
They are also impatient and always hurrying from one place to another.
Not to mention their kleptomaniac issues.

This class made exclusively for Skyrim players that clear out every cave, hoard items in the home chest and even not selling it.
Treasure hunter is an iconic class for me, because any role-play game have that nice feel of adventuring to find rare artifacts, treasures and quests.

The class is empowered with a steed stone. Man, you don't need these mixed armor you found in a dungeon to slow you down from adventuring and exercising in kleptomaniac frenzy! Also, Steed Stone is the best for character with the biggest endurance. And this character is you.

Class abilities:
Treasure Hoarding
Force yourself to bring home these damn 42 ancient nordic battleaxes!
Gain <500> carry weight for <15> seconds with a price of <50> health.

Hit And Run
The typical tactic for any adventurer is just hit-and-run.
Will restore your fatigue <at will> for <10> seconds.


Rogue Class empowers Thief Standing Stone

Rogues take risks more often and only rarely come to harm. They are quick but fragile, unable to take heavy damage, and instead rely on their speed to dodge attacks. Rogues are lumped in with the Ranger class, but more commonly they are differentiated by specializing in melee - particularly with light blades and daggers.

I was thinking long about how to make you evade and dodge attacks as a true rogue should do.
And I figured it out.
Must say, the rogue ability I added is experimental, and I need help with making it work correctly - sometimes it stacks.
So, if you will use it to intentionally abuse Skyrim engine, you will become a god.
It is your choice to abuse it or not, because every class is game breaking enough.

Class abilities:
Stop time for <2> seconds <at will>.
It will be just enough to not get hit, block or counter-attack.
It is not enough to dodge every arrow on the run like you are Neo from Matrix, though.

Blood Mage Class empowers Lover Standing Stone

Here's a nuker! In the late game, you can have cheap spells, but you need like 6 fireballs to kill some bandit.
Imagine a frustrated arch mage that just  can't handle it anymore. He trains in the forbidden art of the blood magic.
Now his magic can't regenerate at all. Even your high elf highborn or super-puper robes won't help.
But you can convert health to mana at will. Be warned, it can, and it will kill you in the middle of a hard fight.

This class recommended for the powerhouses with at least 300 health and 300 mana.
What this give you in exchange? Your destruction and restoration spells are twice as strong. Alteration, Conjuration and Illusion are twice as long.

And yeah, since you become a blood mage you're restless and can't sleep. Thanks, Lover Stone.

Class abilities:
Blood Magic
Every spell twice as strong

Blood Offer
Transforms <100> health to <100> mana <at will>.
Be warned, I am a veteran Morrowind player, and I was killed with this power by a mistake when fighting falmers.


Witchhunter Class empowers Tower Standing Stone

See that high elf arch necromancer that nuked a snow troll and then resurrected him as an undead servant?
Yeah, he's your target. Local jarl will reward you with 100 gold coins for taking care of this outlaw mage.

Remember that witch that joked that you will be a good khajit slave?
You failed to open her expert level lock door to a mushroom tower. But now you can open it!

Class abilities:
Drain all target mana for <60> seconds <at will>.
Now you can beat that nasty slave trader with your bare claws!


Savage of Atmora Class empowers Warrior Standing Stone

Savages are stronger and healthier than any other warrior.
They tend to be brutal and direct, lacking civilized graces, but they glory in heroic feats.
The warrior stone image perfectly represents a big bossy warrior with great axe and shield. 

As Hadvar said, "you shouldn't have been on that cart the minute I laid eyes on you".
Because you are a huge brutal warrior, perfect material for the imperial legion or the stormcloaks.

Very promising indeed! If you choose to be a nordic dragonborn hero, this is a class of your choice!
You even have 50% shout recovery countdown for this role!

Class abilities:
Savage Of Atmora
<100> more health and <50>% shout recovery

Blood Of The North
Close your wounds and regenerate health for 20 seconds <at will>.

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If you can help me in any way or upgrade it with nicer visuals, I will appreciate it.

Since many say that classes are OP, you can add balance patches, but make this mod as a hard requirement, it will help players to uninstall it easily.