Planting wheat or rye will help control erosion until you can establish grass. I am not sure if you want to stock right now due to the chances of the pond going dry during this drought we are experiencing. When you do decide to add fish, start off with minnows and allow them to reproduce a few times before adding other fish. Any type of tree will provide structure but the most common seem to be pine trees or cedar trees. Aeration is not necessary but it may help your fish survive during times of calm, not windy days, during the summer. Recently, we have a pond that wasn't aerated and we suffered a large fish kill.