My experience has taught me one simple lesson...

When you have an idea for a game create it in it's entirety, or at least one full level, keep all your great stuff out of it, just put it together, make it cool, and then wait for feedback, going headlong into a game mechanic that gets dissed by the community is a hard thing to face.

So again what I learned is keep it simple in the beggining and then apeal to the masses.