Ben follow Cody advice is my suggestion. If you are going to start over, be darn sure no upstream water will enter your pond. A levy can accomplish this - easy to build with a skidloader I built many at my farm, but it might cause another issue by eliminating upstream water leaving you with another issue of irrigation/pond levels...dichotomy for sure. Can your pond remain full without that water? Are there additional sources of runoff in your watershed which don't drain upstream ponds? Can you irrigate with a well to make up for lost water through runoff?
If this isn't an option, you can manage a LMB/SMB/YP/RES/BG pond - you will just need to fish it hard for BG/LMB and allow for some shallow vegetation to help YP recruitment. Supplemental stocking of SMB and YP probably necessary per my post and Cody, but it can be done. It would be a great experiment and would benefit the community to experience your success/challenges/etc. along the way. You will need to remove big numbers of BG annually, especially females, and you may be able to play with water levels to discourage LMB spawning per a Pond Boss article a while back. SMB actually dominated the fishery because the lake was drawn down annually after the SMB spawn and while LMB were on their beds. If you wait until LMB are bedding then draw down 4-5 feet you could help reduce/eliminate LMB reproduction/recruitment. Fill it back up once the water temps exceed LMB spawning requirements. Just a thought.
IMO, you are WAY too loose with friends or neighbors regarding fish introduction - it's no joke! I recommend having firm conversations with them all and instruct them to NEVER bring fish of any species, including FHM or GSH, to the pond for stocking or bait. This is your dream, you need to set firm boundaries to preserve it.