I remember when the Planetside merits arrived and how they cause sudden shift in the games dynamic. In other games, it may not be such a bad thing, but in a PvP based game it caused terrible problem when you’d find yourself in a team with mostly supporting powers and very little fire power

I think that modern MMOs introduce these types of schemes as a type of end game content, things to do with your character in-between other endgame content. I’ve recently undertaking some tricky and grindy tasks in City of Villains to gain more badges, alot of them need certain enemies killed other need time spent  in certain areas.

Many will argue that achievements are a complete waste of time, but as introductions into games like EVE, WOW, Guild Wars and Warhammer’s Tome of Knowledge have proved they are becoming a stable part to any online game.

The introduction of more achievements with each release ensures you pick up that top level character once in a while.