Mini-games

Several MMOs use mini-games to make the overall game more interesting. In some cases (e.g. 9Dragons) the mini-game is used to learn a new skill or progress in level. In others the mini-game is essential to the game as a whole (e.g. A Tale In The Desert) where the mini-game is used to create a new item. Still others have them just for fun.

I think mini-games add a diminsion to an MMO beyond simple hack-n-slash. In particular, I think crafting skills should be very strongly mini-game based. Rather than sit around punching the same button over and over, make it a mini-game. Crafting in most MMOs is either minimalistic or repetitive, and making a game out of it would make it a viable alternative to hack-n-slash.