Rift had way too little content. As fun as the classes and souls and stuff was, it technically only had 4 different classes. Not that it even mattered because there was no replayability anyway thanks to there only being several zones. If you made another character it would have to go through the exact same experience all over again. And even the stuff they had to try to break up the monotony like the battlefronts or whatever, there was only like 3 or 4 of them or something. Just everything was too small imo.
And players consume content way too fast. I maxed out my character in Rift in about 2 weeks and then it was just grinding. No company can afford to develop content at that kind of rate. I think the only sensible idea is to do something like EQ NExt is doing and have the players do something repetitive over and over and make that enjoyable. I love playing MOBA's and they have basically no content at all beyond what you first see. Its a bunch of heroes and you play the same 1 map over and over, thousands of times, doing the exact same thing, with no random mobs or anything. But it remains exciting just like every game sports match is fun in its own way.
I think MMO's should do that. Not necessarily just steal moba gameplay, but if you make the game one giant world where people are fighting each other for control of something or to win something, and each battle earns you a little something that chips away at your very long term goal... to me that makes more sense than the current MMO design. Games like Unreal Tournament and Command & Conquer, I played those same games every day for like 5-10 years. They need to transpose that kind of repetition (but fun) in to an MMO world.