It being or not being an MMO really has nothing to do with character development. Diablo 3 is a perfect example. I can play coop with my friend, enjoy the same story, yet if he stops hosting the game I'm not forced to start the game over, I don't lose my drops or gold. A simple solution for this? Don't over think the problem. Join a game with your friend and play, you quit the game? No big deal, you retaining your items or progress doesn't hurt anything. Your friend being level 20 and you being level 5 is unbalanced but it's relative to your situation (it's not being forced down your throat) it's handled the same way it is in any other game RPG style coop game. Level your guy up to your friends level or your friend is going to have to be forced to come back and assist you. This game is a turn based Diablo 3 for the most part, to think it should be handled differently on multiplayer simply for the sake of being different isn't a good argument. Playing an hour in a friends game, only to have to start the game over when he stops hosting is a horrible design plain and simple. There are fixes for this that shouldn't be ignored here.
