1. What's the best dagger combo I can use?
(I'm 100 smithing, so Daedric is most definitely an option. And I'm willing to go looking for anything else.)
Depends on you Smithing, Alchemy and Enchanting Skills. With enchanting maxed out usually Dual Wielding Daedric Daggers is a very valid options since you will have a free choice of enchantmens. Blade of Woe has a slightly higher Damage though. (4 Poins iirc with one handed maxed out). On the other hand Dual Wielding Maces could be an option, too. You will only get 6x Backstab Multiplier but Maces will profit from Fortify One Handed Potions and Enchantments (Daggers won't).
2. What's some good armour?
(I like things in sets, I don't like mix-matching different pieces. I've completed the Thieves guild, and I'll be willing to go looking for anything.)
Shrouded Gloves are a must-have due to the double Backstab Bonus giving you x45 Bonus whith Dual Savagery on a Sneak Power Attack. If you don't mind lacking Armor you could add the 3 pieces of the "Worn Shrouded" Set which can't be improved but can be enchanted.
3. What's a good game style when I'm doing this?
E.G. Clearing out dungeons, my sneak is pretty high due to using sneak while ranging, but I never could get close enough to attack with a blade
There are a couple of factors for successful sneaking: Armor Weight, Weapons Drawn, Speed of Movement, Light, Opponent's facing direction and Sneak Level.
- Eliminate Armor weight by skilling into the "weightless" perks of either light or heavy armor
- Daggers ar for all matters considered "silent" so you should have no problems here
- Speed of Movement detection can be negated by the Sneak Perks
- Light/Facing: Get "Throw Voice" Shout and direct enemies to dark corners in case of doubt - or just shoot an arrow into a dark corner
- Max out sneak level (because the "Shadow Warrior" Perk will allow you sneak attacks infight. Incredibly overpowered)
- Enchant "Fortify Sneak" on one or two Items. (Careful though: It seems you can boost Sneak into regions where it creates kind of an "overflow" resulting in a worse sneak value than before. Possible this value is 255 but I can't confirm that for now).
In General maxing out Alchemy, Smithing and Enchanting would give you Access to the Strongest Weapons and Armor Enchants ingame, if you're up for that.
Do NOT enchant "Fortify One-Handed" when using Daggers. They will not benefit from it.
Usually you will one-shot pretty much anything with shrouded gloves, legendary Daedric Daggers and the Sneak/One Handed Perks. IIRC you can get to 15,000+ Damage attacks even without Orc Racial or Marksman Potion (the potion is bugged and boosts Dagger Skill as well).