I am on Marilith and honestly I am enjoying it. Yes it is a bit slower but I like things like that. Waiting a bit longer for a queue to pop doesn't bother me. I just take care of other things that need doing while I am waiting. Being a solo player I don't really miss the social side of things. This works for me and how I play the game.

I am firmly in the camp of things will improve with time and come 7.0 will likely take a big jump as people deal with log in queues for a new expansion.