That BG does have good color!
I keep fairly good records of catch, cull, release, length, weight and WR on fish from my pond and have since 2013. But it is much smaller (only 4 acres) and my WR started at 83% rather than in the 60's. I know that culling 25Lb per acre of underachievers for the last 3 years has upped my ave WR to 90%. I have to think culling AT LEAST 25LB per acre, or more, would help your situation. But I am glad I don't have to work over a 20 acre piece of water by myself! There are some great pond managers around this site, one of them will be around soon I bet. They will have some suggestions, and pointed questions, suited to your situation.
Do you have plenty of structure for the YOY BG? And do you feed the BG?
I, like BOCOMO am curious why a shock boat is a liability in your case? I wish I could find it in the budget to do one here.
