How about public funded elections where the amount of funding is based on the level of office being run for? The problem with no money in elections becomes with what is designated as "money in elections"? If one candidate cannot afford to travel to make appearances and the other is wealthy and can, does that count as money in elections and a non level playing field for example? It definitely gets very complicated.
Make it simple then. Expand the FEC both in size and in scope.
Provide the candidates with staffing, marketing, access to media, and travel commissurate with the position being run for, but make it equal. Barack Obama gets the exact same as Joe the Plumber. That's what they get to use period. Doesn't matter how rich they are or what they have access to outside the system.
Considering the looming apocalypse of college graduates with no job prospects this shouldn't even be hard to fill.
The only way you will ever level the playing field in politics is to totally ban political speech outside approved channels and methods. I don't think you'll ever be able to pull it off.