Buzbe, with a lake that size I would think it would take a lot of fish being introduced to populate it. If it has all the normal delta predators(bass gar grinnel catfish) it should keep the numbers somewhat in check. You will need some tight cover for the crappie to hold in while they are small. If they aren't regulated in a few years there will be a ton of small fish in the pond. If the bass are healthy and there is plenty of forage, I think you would be ok. But I'm no biologist. Best bet would be a good pond manager to tell you exactly what will be the best for your particular lake. Some will come shock it and see what kind of fish it's holding and populations. But as far as depth, lake I live on has a max depth of 9-10 ft and has a really good crappie population.