Years ago I had access to a private sand plant that had 3 separate ponds. Most of them sound the same as you described, except only about 30-35 ft deep. I used to throw small slider worms and kill them. Working the drop offs, any points and the one pond had a drainage ditch that ran into it, if the water was running than the fish would be stacked up on it. Most of the bass were small in there. I assume it was because of lack of forage. 70-100 fish days were not uncommon. Mostly dink’s but I Managed to pull a few 6+er out of there. I sure do miss that place.