Content they add won't really change much. It is their gearing model that is the problem. Even if you add super hard dungeons, players that don't do hard content will still get comparable raid quality gear if they wait long enough.

If you have other jobs to play on the same character, the model works decently for you since you can gear something else during the catch-up patch while getting the upgrade items for your main.

If you are a raider and only play a single job you are pretty much done or close to it when the catch up patch comes up since all the gear is useless unless there are new BiS items thrown in somewhere.