Skyrim vanilla combat is total ass. Personally I don't care much for script-heavy or even script-light combat mods, they make some things unnecessarily complicated or tedious. I also tweaked a few other game settings I thought were ass as well.
Here are a few small things I've changed:

Jump height from 76 to 100
Maximum amount of summoned creatures to 5
Maximum arrows sticking out of a body to 35
Starting Skill level to 1
Maximum smithing improvement for armor and weapons to 15
Maximum selling price multiplier to 1.05
Minimum buying value to 1.00
Maximum physical damage reduction by an armor set to 100 percent. No way an iron sword can damage Daedric. That's like poking a bodybuilder with a f**king toothpick. 
Some people have tweaked how much armor rating per point is changed (like the default 0.12 per point of AR), but I just changed the maximum points per upgrade level from 10 to 15. Very small changes but they have the ability to change the way a battle goes.

The price changes were made so you don't spend 750 gold at level 5 on a crap piece of armor. I found that the assiest part of vanilla Skyrim, it wasn't that bad in Oblivion.

Installation: Use your favorite mod installer or do it manually.