We did this topic before. Albeit its been a awhile ago and I probably only remember it because I posed the question at the beginning of the year.
»What would your MMO be like?
That said. I would still like an open character design ala Skyrim. This parts important, however it would be impossible to balance, but would accommodate different playstyles for different folks. Which could result in a large population of "Battle Mages" though I would hope that more people would just find a style they like, or even just have fun experimenting with.
Questing.... I like how its being done in GW2, so I'd like to keep it simple like that. Though I think it could be a little more dynamic. Say for instance, incorporate factions into the mix as well as an alignment system. So now, instead of just saying the villagers, you could be attacking the villagers along side the centaurs or bandits. Assuming you have the right alignment and factions to make it work. That would make for some hellafun escort quests if you could be raiding the escorts instead of strictly defending them.
I know not everyone is a fan of PvP... myself included, but I actually like this idea.