Wow...really? I didn't know that was possible. Learn something new everyday. Trout prefer running water, like a race way. But they can be adaped to ponds. They just are jumpy...alot. If you are close to a stream try a minnow $20 at Cabelas. I caught them as a kid with a net in a stream. About 2" long ones.
I don't have any experience with cherry shrimp. But there are colored mystery snails that breed like bunnies and would help with the clean up of the tank. Thier babies get decent prices on ebay and the like. I bought some online, and they ship well. Increase the volume of the water, it's slow to heat up and slow to cool off, this will eliviate some of your summer issues. That's why I ulitmately went outside with mine. Live food actually increases apetite. It makes them want to eat more. Kinda like when you fry hamburger and onions together...makes the mouth water.
BG are surface eaters that will most readily take food off of surface. They can be testy at breading time. Would encourage you to put about 2" of course sand on bottom of tank/pond as they are nest builders. Both of your species though are avid meat eaters. They won't hesitate to eat just about anything, and what they don't recognize they will eagerly taste as a way of exploring it. Cheerios works good to. Not sure of nutritional value, but fun to watch.