This scenario isn't unusual in an unmanaged pond. The correct management tools are skilets and hot grease. You don't mention bluegill or minnows so I assume there is no forage base. Thus, the predators are surviving by eating only their progeny.

Crappie can ruin a small pond. They spawn earlier than bass, have a hinged jaw and are direct competitors. Keep all of them. Also, start eliminating the small bass. They are their own worst enemy. The "average" pond will carry no more than 100 pounds of predators. And, that assumes a good forage base.

Fish it hard to eliminate the excess small bass and all crappie. Don't worry, you will have a tough time catching enough. It is work and you won't catch them all. Over time you should start seeing a larger average size of bass. At that time, stock about 300 or more six inch bluegills. That will go a long way toward creating a balanced environment.

Yes, you can (and do) have too many bass. You are describing a typical bass heavy pond. The fact that they hit minnows so readily means they have nothing else to eat and are starving. Ignore the catch and release mantra.