
If you decide to go this route, I'd recommend going with illusion + alteration. Using robes is also a very viable option, depending on your character set up.
You can still sneak effectively once you hit level 70 and get the conditioning perk. (You are a bad thief if you get caught off guard ) ) Tower of strength stops you getting knocked back if you get caught off guard. Light armour still gives a decent armour rating, so if needed you can go toe to toe without taking a huge beating. Is pretty important for you running away, positioning etc. Windwalker is great for a thief, your stamina regenerates 50% faster. Leveling your armour takes longer than you would expect. As a thief you don't tend to get hit often, so That light armour weights nothing is at skill level 50, in heavyĪrmour, it is 70).
You are less detectable in lower levels with light armour (the perk.
The thief guild provides you with some nice light armour. I am playing a Khajit thief and I use light armour.