After you get the type of chao you want, go to a stage which u can get lots of esy money on (most Sonic/Shadow stages) and give it alot of chao fruits. This is a good method to train all of your cho stats at once fairly quickly. If you have any other training methods feel free to share
Rapidly collect chaos drives from Iron Gate/Prison Lane hard mode for the quick status, the chao fruit method takes some more time, but raises stamina too, which we all get too lazy to raise X_X
Quick ring trick and the Stats trick with skeleton dogs bats and Half fishes to maximize stats without animal parts leaving you free to experiment with them.
Oh, and the mushrooms. I think they raise double stamina.
