Tim, from what I read Big Channels can be quite aggressive on Small Panfish such as crappie and even bream. Just read the thread called "Too Many Big Channel cats" I think it's called.
Keep your channels if you like them or bass will work as well. Although I did here you say the Channels were eating the bass..
Any way I believe the most important thing you can do for a crappie fishery is yes FISH THEM HARD!!!
Then make sure you have astablished a Very GOOD Forage progam...mostly with a fertalization and a good threadfin population.
Remember what the underline thing that most of these experts are saying, "these fish will eat you out of the house if you are not carfull."
