Graphics wise I have a few:
- Skyrim Flore Overhaul
- Static Mesh Improvement Mod
- A Quality World Map
- Skyrim HD -2K Textures
- Footprints
- SkyUI
I also have ESBoost installed. It's a... uh... series of settings that uses different graphical adjustments for shadows, lighting and the like. I don't really know how to explain it. Before that I had "Realistic Lighting Overhaul". I tend to be a bit hesitant about graphical mods as I don't like soft filters, depth of field, motion blur or how dark some of those mods make things. It is best, I think, to look around and see which ones you like the most.
For armour and weapons:
- Perfect Legionnaire - Imperial Armour Reforged (Might have been added because of another mod)
- Daedric Lord Armour by Natterforme (Because Morrowind Daedric armour looks so neat)
- Immersive Armours
- Immersive Weapons (Immersive is a word thrown about quite a lot with mods. The armour and weapons look nice though and add variety, though some stand out as unfitting for Skyrim)
New Quests:
I don't have mods for the quests themselves, but some of the overhaul mods I have add new quest lines
- Undeath (Adds quests and skills to becoming a lich. Needs a compatability mod for Perkus Maximus)
- Moonlight Tales - Werewolf and Werebear Overhaul (Adds new mechanics for were creatures. My favorite is random time after nightfall to transform.)
- Vampiric Thirst - Dawnguard Edition (New mechanics for vampires. A lot of abilities like increasing strength, jump height, toughness as well as increasing reflexes/slowing time and gaining power the more times you feed. Also doesn't make vampires overly pretty, keeping them how they look in the base game.)
- Immersive College of Winterhold
For bug fixes the only one I really have is the "Unofficial Skyrim Patch". Anything else is to fix specific issues between other mods. There's another called "Skyrim Shadow Striping Fix" but I don't know whether that problem continues since I got my new graphics card.
I don't have any mods to modify steath itself, though:
- Perkus Maximus - Maximum Perk Overhaul (Changes perks across skills, so it does have an effect on stealth.)
That's all the major ones really. A few others like "Moonpath of Elsweyr", "Wyrmstooth" and "Falkskaar" but I can't remember enough of those to comment much.