I didn't take much notice of the story/lore in the beginning, some of it just seems generic but almost all the other options kept me engaged in The Elder Scrolls. I chose Open World and Customization, the latter for me, for any game that I play I am always interested in customization. Of course there are genres of games or even those in some way similar like Zelda that I don't mind if there is next to no free customization, but the stories usually compensate.
I think for the question, the most well-suited answer in most people's idea would have to be customization or open/world, who knows maybe one-day I can get emerged into the lore properly, until then I don't mind strolling around inns, sitting down, having drinks and listening to those Bards flick the strings.
But knowing all the work gone into all the Mers' background I guess I might choose Lore as a third option, who knows...
...
On second thought, I think my third option would probably be my attachment to the spell schools, i.e. Conjuration
