I find my 4 inch burundi have been acting typical from what i hear. I had one fish that once the fish reached 2-3 inches seemed to have a big growth spurt compared to the other tankmates. He also got meaner and his color is now different compard to the other 4 fish, darker blue (more of a navy compared to Ice /sky blue of other fish. He also is the only front in the tank that will blanch a couple shades lighter and attack his reflexion violently. Right away he also selected two other fish to vent 80 percent of his aggression at, he herded them into the far corners of the tank, never lets them out of that area for anything but eating. He is allowed into their area but they are never allowed out of their area into the alpha's territory. The other 3 fish he will chase and bully but lets them stay in his area as long as they yeild and avoid him.
None of this is 100 percent foolproof. I heard that once this happens if you remove the "alpha" the next dominant male will step up into that position and have the growth spurt and faster development. You then remove that fish as well and if another male is there he will step up. You keep doing that and eventually you will have a good chance of having all or nearly all females in the tank. This is not a fast or fool proof method. But for people who are not experts at venting who have numerous juvie fish this is a way to help reduce the odds of too many males in with the females you hopefully have picked out etc..
Hope this helps.