The biggest thing, which was not mentioned here, that the current state of MMO's seem to have destroyed, is the social aspect. In an attempt to make a game really easy to get into and started, they've created games where people play beside other players, but not with them. There are no bounds created, and no team work needed until you raid. This is what I think needs to be worked on the most.
That said, most of the ideas sound cool. Btw, Neverwinter has content created by players as well, though it sounds like this has a different idea on how players create content, which is more in line with a living world, instead of player Dungeon master instances that Neverwinter has.
One other thing that I would be interested in, and that is slower paced combat. Back in the early days, slow paced combat made combat more tactical, rather than mindless. It also slowed down the pace in which content is absorbed. Combat can be fun, even if it isn't moving at a frantic pace. It allows players to talk mid combat and use team work more.