If you can get the RES established with a good head start in size, I think you could have RES for several years before the CC get, say, 5 pounds and start eating the larger RES. The RES could also add to the forage base for the CC. I have no real experience here...just my 2¢.
I think HSB would be a good choice for CC YOY control. My HSB cleaned up the FHM in the pond in a matter of two years. They did not, however, do a lot of surface pellet eating. So little that I could not tell if they were going after pellets or going after FHM's pushing the pellets around. After year #2 with barely a minnow left, the HSB seem to stop hitting the surface as much at feeding time, but you could see the flash of their bodies about 18" down...maybe pellet eating, maybe eating HBG YOY, or both...IDK. If you do put in HSB, you will want to use heavier line (like CC) to get them in. They are a freight train on the line.
Adding single sex LMB will always be an option. You'll just have to wait and see. The hardest part that I have found about pond management is being confident with any sort of population estimate. So often I wished I had a pond void of fish just above this one so I could drain the stocked pond, count the fish, and then fill it back up. Probably would not be a good idea in reality, but curiosity is killing this cat!
