I have fallen directly as a result of clipless I think 4 times now. It ended up that I had crappy pedals, and now I can deal with them very easily, they pop out with no effort at all (on a low setting).

As for intersections, I usually unclip both feet to stop, and then start by riding out unclipped (pedal in the middle of my foot, as if it were a flat regular pedal). Once I am out of harm's way and picking up some speed, then I clip in. This has always made me feel less nervous anyway.....