Who cares how quickly you finish the game? Why is it your problem anyway, let people play how they want to.
I for one just wanted to kill Alduin, and I did at 48 hours in. Plus I wanted to get it largely out of the way.
I was really let down with the ending though; Alduin was piss easy at level 36, and the fact that there was no loot pisses me off no end.
Alduin is unlootable; there goes me hoping for some epic sword called 'Alduin's Fang' or something along those lines, you can explore Sovngarde which gives NOTHING bar some bloody food, and then you get two shouts to call either Odahviing or some ghosts to help you.
Fuck that.
I've decided to make my own final Alduin loot weapons using enchanted Daedric ones, just renamed.
Currently I'm doing that Gauldur Amulet pieces quest, but can't find out how to open the door to Saarthal....