As always, thanks for the feedback. I plan on installing them next weekend, so I have a little time to adjust.
Sunil, you make a very good point about weeds growing up from the pond bottom. I have about 8 ft of depth from normal pool with which I can still work (the pic below is now about 3 or 4 ft deep with water). I still think that the area with a 3:1 slope is on target, but how deep should I set the bottom of the cribs if I have about 8 vertical ft of dry zone left to work with and the cribs are 2 ft tall?