Question for the assassins:
Gear: Ok I know light armor is a must. I'm assuming light armor as a set, no other types in between.
Nope, light or heavy, light is better for stealth classes...theres an awesome Light Armor perk that gives +50% stamina regen when wearing full light
Weapons: Which is primary/Secondary? Ranged/Melee? For Melee, do you use daggers exclusively or dagger/sword combo? I'm running with a fine iron and fine steel dagger atm, with points shared between 1hand combat and archery.
I run with 2x Glass swords for when the skooma hits the windmill, I have 2x daggers enchanted with Soul Trap for stealth kills and a Glass Bow for ranged pewpew/openers
Spells: Do you make use of them? Healing? And do you only equip them when the need arises? Or do you roll with one equipped?
I run with Fast Healing (+50 healing), I only equip it (and dual wield) when in need of healing/running away/after combat. I've played around with some of the destruction magic, the fire is great against undead
Elemental Fury for melee combat when not in stealth, Throw Voice for distracting enemies when stealthed, Ice form for CC. I use Aura Whisper the most when creeping around. If you're still squishy, the Disarm shout is great against those 2h mofos that decapitate you
Magicka/Health/Stam: So far I've upgraded 3lvls of Health. Should I focus on others?
Stamina is what your power attacks (main dagger kills) require, at your level I could get 1 maybe 2 attacks off, now I can get 8-11...I have 240 stamina though. Health is probably the best stat because once you get strong enough (stealth 15x damage perk), you'll need the health for when you get spotted
If you put points into Archery at all, theres a steady aim perk that drains stamina A LOT
What should I focus on as professions/skills? I'm lockpicking everything I find (successfully so far), but I'm wondering what I should put points into?
In fear of making your character hopelessly OP and boring, I'd suggest not power leveling these 3 professions - enchanting makes your enchanted weapons/armor stronger...alchemy makes your potions/poisons stronger...smithing makes the best armor and weapons
The synergy with these 3 skills can reach game breaking levels
I haven't found the lockpicking perks worth while in my opinion... at 98 lockpicking, master locks open with ease (without any perks in the tree)