Since I got Skyrim this time last year, being a Morrowind -> Oblivion veteran (I'm not old enough for everything before then) I've notched up 467 hours, and I've never gotten more than half way through the main quest. You see, from the start it was all about playing a Dunmer mage, it always has been. After about 420 hours of that, and some Nightblade too, I finally started playing around with some Nord melee types, of all kinds, a playstyle I've never really stuck with throughout the whole series. Yes, these big Nord lads sure are handsome, and yes, the melee kill-cams are immensely satisfying, but time I get to level 20+ having only completed a handfull of quests I bore myself into starting over. Been about 5 warrior Nords now. I've just rolled a new Dunmer tonight, and my spell fingers are itchy...
I know this will probably be contentious, but I long for the old class system. It gave a sense of boundary, and purpose, helped one to roleplay and get into and commit to a character. Skyrim is great, but I think the character-class issue was a misfire. It dosn't really work as well as it should; I think a little bit of a 'class' system which compliments how things work now would be of benefit to the game.
But hey, at least I'm not relapsing into tobacco, an endeavour in which this game has proven invaluable.