Into my 0.2 ac minnow pond I put around 14-20 tilapia in it each year. The pond has lots of large rock shoreline habitat. It has thousands of minnows that I have to regularly remove annually to keep them from being over abundant so others can grow. I feed the minnows ground fish food daily and have high production. I would first try the tilapia. I think some tilapia varieties/species could be more predatory that others. Species might make a big difference. In my experience tilapia will maybe only eat small minnows when all plant materials are eliminated. They have to eat something when all preferred plant foods are eliminated. My minnow pond usually has quite a bit of nuisance algae and Chara. The really good thing about using tilapia is they keep the algae very low, you fish them out and eat them early fall, and remaining ones die each year so if you don't like their behavior you can very easily use a different fish next year. Adding some of the other fish species may make it difficult to get those trouble makers out. Also consider redears. they have low numbers of offspring, and young ones can be transferred to the main pond. Also consider golden shiners. Adult shiners when abundant may eat some small FHM fry but you should still get lots of FHM each year. GSH should also make very good forage for your main pond.

The male bluegill idea is a good one but if you make a mistake is sexing them be prepared to start over or deal with many thousands of starving small 3"-4" BG that will eat lots of FHM fry. IMO I would stay away from CC because they will find a way to spawn in ponds and thousands of them will eat lots of small minnows be prepared for that. CC spawns can be very successful in a pond without bass and other predators eating the CC fry and fingerlings. Larger CC will create their own spawning cavity in sides of a dirt bottom pond.

Depending on which other fish you decide to stock the appropriate type and amount of habitat becomes very very important for good FHM survival.