When you take out the progression aspect from an RPG, then you're left with storyline and game play itself (MMOFPS). Now I definitely don't mind good story--it's RPGs we're talking about, so story should've been the first focus anyway.
Otherwise, we can always focus on the game play aspect. People keep coming back to action games because they like the actual action. Personally, I think World of Arena/BGcraft, Guildwars and WAR is a great example of big name games focusing on the action. If the game play itself is satisfying (for whatever reason) then it works just as well.