I actually have a few ideas for a MMO of my own, if I can ever get a development teams and the money for it, but I don't have enough for a full game. Maybe more ideas than Destiny or GW2 at launch, but not enough by any means to even pitch the game to myself.
On the other hand, I have a slew of ideas and details swarming around in my head for a (solo-play, classic turn-based style RPG) game trilogy I'd love to head the development of, despite knowing nothing of the development process myself since I'm more of a story writer. xD