Lots of variables here. I have only one pond so I learned from the good people on this forum that if you had bluegill of ANY type that you needed predators that could keep up with them (mainly LMB, nothing else). Likewise, the LMB spawn so fast that they needed BG to keep enough spawns going per season to feed the hungry LMB.

You have a luxury. You have multiple ponds so can do multiple 'balance experiments'. The 'few BG' that 'don't spawn much at all' is going to wreck your balance. The HBG don't spawn as much as standard BG, but the next generation will include hybrid becoming NON-hybrid green sunfish since the parent to HBG are greensunfish. The green sunfish will become another 'predator' and really tip your balance and make it hard to get back.

So if you want a unique northern pond stocking plan then I would first FIND OUT if you have ANY LMB. ANY....!! Don't rely on catching them with hook and line.

If you figure it is a crazy mix of fish already and you want to keep it that way then i wouldn't stock anything until you know what is in there. Build or buy cages and start trapping. See what size classes of fish you have. Seine the pond.

But if it was me (and I'm only one relatively inexperienced non-expert), I would use your drain valve. It will rapidly get the water down, which makes it easier to use a seine net and dip net to get your fish out. Sort them, if you have desirables you can either put in cages in one of your other ponds for later restocking, or you can put the catfish in another pond that is later going to be a catfish pond etc. Minnows can be put in any of your other ponds. Maybe you decide to keep all your YP in a holding cage till you are ready.

Then plan your current pond. If it is SMB, YP only then make sure you have only those species. Then add lots of forage sorting EVERY FISH BY HAND to be sure you don't tip the balance the wrong way again. If the SMB and YP plus some healthy minnows become a balance that you like, then you you can add a walleye or two for fun but you will be in control. Research if Tilapia are allowed, they are a fun forage fish, often available from a local aquaponics outfit.

Experiment with the CC in another pond.

I don't read much about rock bass on this forum. I assume you will catch those in another lake and transport to your lake? Someone else will have to tell you about their spawning, their ability to exist alongside SMB and YP etc. I have not heard much negative about them.

I bet others would have good advice too.

For snails, depending on your winters and your latitude, RES may not survive. Pumpkinseed are the preferred northern fish to eat snails. A few fish farms in the midwest have them. Not sure how to source them by you. But if you can get RES they have many advantages in a small pond.