Beautiful site, Andy. Gets the same annual rainfall as Abilene, Texas. Next thing I would do is pothole in the middle of the pond sites and get the soil analyzed. It would be great if there is high clay content in the soil at and just below the proposed bottom of the pond(s).
There doesn't seem to be significant erosion and you've got ample fall across the site. Looks like it may have been a tad overgrazed in the past?
Exciting project.