Since you already had a fall even without clipless pedals;
I would recommend the Click'R model that's supposed to
have an easier release. After you get them; practice,
practice, practice unclipping and clipping in. I used
Shimano's M520 for about 5 years. My MTB shoes wore
out and I switched to Speedplay X/2.

https://www.youtube.com/watch?v=FFyX...IoDLA&index=46