If you're serious about developing these ponds into an enjoyable recreational fishing paradise perhaps consider really digging into them before putting any new fish in.
What is the water clarity? You can use a GoPro camera to shoot video underwater if clarity is a couple of feet. This will allow you to see everything that is in your pond, therein you can decide if you want to drain them, remove anything you don't want in your ponds (such as the vehicle, trees, etc.), set fish habitats, fill them, and stock them.
