I would be very okay in a world that offered 80% of its content as group centric activities (6 to 10 people). You can not put in enough dungeons in the world for me, love them.
The issue I see in modern MMOs is all of them follow the same pattern now, Mechanical based raids from 10 to 40 people, and you are judged by your item score. So damn boring if you look at the big picture. Give me a game where I can progress over a LONG period of time, and get involved with every bit of the world. Let me do it with a large group of friends and create moments. Have dungeons that take a good bit of work to complete, not a 20 minute speed run.