The best falafel recipe I've ever used is out of the Stephanie Alexander 'big' cookbook (can't remember what it's actually called, I just call it the big orange bible).

I'll see if I can dig it out once E is asleep tonight. The trick is, use dried chickpeas, not canned, and lots of herbs. Dried chickpeas, soaked but not cooked until soft, then pulverised to a kind of 'gritty' texture rather than fully pureed, results in very very light falafel. I find that using tinned chickpeas results in a very dense falafel.