I don't know if theres been a topic of this (probably has), and I'm to lazy searching and looking for what I am about to ask (sorry for that), so here it goes;
What is the most rewarding class, in terms of playability and fun-factor? I guess this is a 'taste-matter', what you like to play as etc, but please share your views

I have made 4-5 characters (thief/assassin (lvl 11), mage (lvl 5), 1H shield-warrior, Death Knight-ish (lvl 12, heavy armor, 2H, illusion magic for fear, conjure and destruction magic) and a 'Jack of all trades' (lvl 40, my first.. didnt know what to pick when I first played the game), so I tried to re-roll, and havent come up with what I want to stick with.
its not a problem, sure, I can play with all if I want, but I keep loading another character after 10m of gameplay, of 'unsatifyness', or because I'm uncertain. and that takes time.
I like the idea of the Death Knight (beeing a spellcaster with heavy armor, and I can rush in and crush skulls with a big great sword if I want), so I can variate the gameplay some, but I find that the destruction magic (frost) is very weak compared to sword-bashing and archery. Is it like this later in the game as well? (bare in mind, he's only lvl 12, and no, I havent used so many perks in the destro tree yet)
Thanks for answers!