The new difficulty options menu from Ver. 1.11.36 covers many bases already. Still, certain tweakworthy aspects of the gameplay remain untouched - the amount of resources needed to complete research projects (eg  for Weapons, Suit, Helmet, Pack, Food, Chems, Cooking, Outpost...) is one of them.

DOE Research makes all research projects require a significantly higher amount of resources than in vanilla (the required resource type itself does not change). The mod groups the resources into two categories: farmable and non-farmable. The number of required farmable resources is increased in much higher steps (depending on difficulty level: 5x, 25x or 50x) than for non-farmable reources (depending on difficulty level: 2x, 5x or 10x).

The following resources/pre-products/special items are considered as non-farmable (and the rest farmable), partly because their own crafting would require non-farmable ingredients:

All food items, Genetic Material, Caelumite, Aurora, Chambass Oil, Quark Degenerate Tissue, Emergency Kits, Trauma Packs, Heart+, CQBX, Battlestim,. Addichrome, Synaps Alpha, Hyppo, Reconstim, Infantry Alpha, Squall, Boudicca, Battle Up, Panopticum, Frostwolf, Whiteout, All special hearts, Paramour, Neurajack, Addijack, Red Trench and Panacea. 

This results in the following dificulty options availabe to choose from in DOE Research:

[Vanilla      1x resource cost farmable   / 1x resource cost non-farmable]
Hard          5x resource cost farmable   / 2x resource cost non-farmable  |  +0.5 % suggested XP Modifier
Very Hard 25x resource cost farmable / 5x resource cost non-farmable  |  +2% suggested XP Modifier
Extreme    50x resource cost farmable /10x resource cost non-farmable | +3% suggested XP Modifier

Hard is still viable without outpost building (unelss you use eg DOE Resources to shut down or limit resource vendors at the same time) - Very Hard and Extreme make outpost building and industrial production a neccessity. Research becomes a long term goal now to work towards to. Something that makes it worthwile to go out there into the blackest sea, set up a connected outpost infrastructure and explore remote moons at the edge of settled Systems on the hunt for exotic resources, in the ground, in plants or in creatures ;-).

"I dislike this", FPI Agent Greystoke 

XP Modifiers can be realized via XP Unchained.

Please note that when using DOE Research with an existing savegame already started , ongoing research projects will show as not completed in the UI even if you finish them. To avoid this UI bug it's best to start a fresh game on level 1 with DOE Research installed right from the start.

How it was done
 DOE Research is an .esm mod, made with xEdit. No scripting involved. 

Installation

• With Starfield's June 2024 update (Creations) installation has become much easier (the Plugins Enabler mod and therewith SFSE is no longer needed to install this mod)
• Just download the mod version of your choice (currently Extreme, Very Hard or Hard) from the files section, unzip it and place the .esm file into your game's data folder 
• Double check ingame in the Creations menu (available from Main Menu), then Load Order submenu, whether your chosen .esm has a checkmark. Ideally move it down the load order, so that it is loaded last (this prevents it from being overwriten by preceding mods)  
  

Credits
Shout out and big thanks to maddensterror who did something very similar - albeit much less extreme -  here:
More Challenging Research Requirements at Starfield Nexus - Mods and Community (nexusmods.com)
Also FriarChris has done a great job here with Research Redone at Starfield Nexus - Mods and Community (nexusmods.com), which differentiates by rarity of resources 
Without xEdit and Elminster's work of a genius all this would not be possible, so, many kudos to Elminster and team.

The whole DOE Series and friends
DOE Resources
DOE Resources at Starfield Nexus - Mods and Community (nexusmods.com)
DOE Sell Price
DOE Sell Price at Starfield Nexus - Mods and Community (nexusmods.com)
DOE Starpower
DOE Starpower at Starfield Nexus - Mods and Community (nexusmods.com)
DOE Loot
DOE Loot at Starfield Nexus - Mods and Community (nexusmods.com)
DOE Ammo Rarity
DOE Ammo Rarity at Starfield Nexus - Mods and Community (nexusmods.com)
DOE Ammo Prices
DOE Ammo Prices at Starfield Nexus - Mods and Community (nexusmods.com)
DOE Skill Progression
DOE Skill Progression at Starfield Nexus - Mods and Community (nexusmods.com)
DOE Research
DOE Research at Starfield Nexus - Mods and Community (nexusmods.com)
DOE Less Shortcuts
DOE Less Shortcuts at Starfield Nexus - Mods and Community (nexusmods.com)
Replicant
Replicant at Starfield Nexus - Mods and Community (nexusmods.com)
XP Unchained
XP Unchained at Starfield Nexus - Mods and Community (nexusmods.com)
Sneak Damage Hotfix
Sneak Damage Hotfix at Starfield Nexus - Mods and Community (nexusmods.com)
Equipment Level Requirements (ELR)
Equipment Level Requirements (ELR) at Starfield Nexus - Mods and Community (nexusmods.com)
NGXP Plus / NGXP Plus Risk
NGXP Plus at Starfield Nexus - Mods and Community (nexusmods.com)
Minimum Enemy Level
Minimum Enemy Level at Starfield Nexus - Mods and Community (nexusmods.com)
Fauna Protection Initiative
Fauna Protection Initiative at Starfield Nexus - Mods and Community (nexusmods.com)
Spongecop
Spongecop at Starfield Nexus - Mods and Community (nexusmods.com)
Building Rarity
Building Rarity at Starfield Nexus - Mods and Community (nexusmods.com)
Minimum System Level
Minimum System Level at Starfield Nexus - Mods and Community (nexusmods.com)