I played as thief, and it was really too easy. I made it more fun by trying to sneak past everything and kill as little as possible. Simply rely on pickpocket and such to grab keys and loot chests behind their backs, as well as using bow to make noise so enemies run over to investigate then sneak-roll past them.
That was alot more fun than the constant x30 damage backstabs.
I tried all sorts of styles, from 2H melee to bows, backstabbing, shields and spells.
After trying all different playstyles I finally restarted as the playstyle I enjoyed the most;
Nord, using sword + shield, heavy armour, as well as restoration spells and some destruction and bow for long range hits.
I like the combat with shields, timing your attacks and bashing spellcasters. Combined with the wards from restoration you get nice defense against casters, and dragons doing flyby attacks. Also really nice to have healing, and healing hands as well. Alot of times I stay in cover and heal Lydia while she is tanking some nasty caster boss.
I think of it as a paladin type of class. The versatility is awesome. My perk investments are going to be in block, 1H, heavy armor and restoration. But having played alot of different roles I know where not to put in perks at least, which means I'll have alot of perks to spread out into more trees ad I gain levels.
The only thing I'm somewhat torn about is the armor choice, as I both like the protection from the heavy armor, but I really like the mobility of light. Might have to plan out perks so I can use both

But, on topic, thief is fun, but the fun factor wore off fast once you can oneshot everything.
So no, not a thief, assassin or sneaky archer