Personally i would not have crappie in a pond that size. for one thing they are going to spawn earlier and compete with your bass for food. I guess if you harvest them continually and stay on top of it it could possibly work. Maybe if you stock them after the bass are already established. personally I would stick with BG and LMB.

As far as the feeder goes I think one feeder should be fine. you assume correct i think when you say the fish will "train" themselves to the feeder.

They feeding will certainly help you BG spawn more and be more healthy. The guys here say to use the higher protein food, not just the catfish kind.

Good Luck!!