What gaming Universe would you like to have its own mmorgp?

  What is mmorpg ? 

Massively multiplayer online role-playing games (MMORPGs) are a combination of role-playing video games and massively multiplayer online games in which a very large number of players interact with one another within a virtual world.    

But the real question is, what universe never got any kind of mmo, but actually could be awesome to have one ?    Since first playthrought of The Witcher 3, i was thinking abaut how good ( and how bad) could be an mmorpg in Witchers Universe. Where you start,as a peasant and climb your way up not be doing quests, but doing daily stuff like training, fighting bandits or even gathering crops. The problem starts  when i realised   it's not only universe that i loved some much but also Character that are in THAT universe. Together they make this sweet recipe, but apart they could be as bad as any other short lived mmo.

Do you think there is any other franchise that could have interresting mmo game or that has one but never should have any from the start?