Interesting, I've tried to play as a thief for a bit before.
Trying to follow tradition and in game context. My character basically likes to play tricks, being underhanded, avoids direct fights but will go or approach wherever seems to have some sort of treasure or so. I basically steal but maybe buy something from time to time and playing it safe for a bit before doing so. Not sure how the chances and modifiers if any at all with regards to stealing but I'm just trying to wing it as I go...I've been caught a few times now and when that happens, I spend a few days outside in the wild before going into the town and playing it safe for a bit then doing it all over again.
I'm trying to properly role play as best as I can but I admit that it is pretty tricky with how the game itself is. I wish the thief started with a dagger instead or like have the option to get one. So far, I don't think that's an option in the game.