Ghost shrimp also get big in a short amount of time and would probably predate on your badis.
There are a number of species sold as ghost shrimp. The ones with tiny feeder claws don't get terribly large (2" or so for females, though I have one jumbo specimen that topped out at about 2.5") and are more or less incapable of predating on an adult fish, even a little one like this. There are others with longer arms and slightly bigger claws that maybe could but almost never do unless they're badly underfed, and there are also the red claw macro shrimp that cause all sorts of mayhem and are extremely aggressive toward everything.
I've got a hundred or so adult ghost shrimp in a 30 gallon tank; they don't bother each other or their offspring, I never find chewed up corpses or shrimp being attacked, and the juveniles aren't harmed by the adults in any way that I've seen. I suspect that a lot of the aggressiveness that people have reported is due to species misidentification, scavenging sick or dead animals, and in the case of shrimp tanks, lack of feeding (as they aren't algae/biofilm pickers but scavengers and need feeding.) I feed mine daily with fish food or sinking pellets and they seem quite happy with the situation.
I wouldn't be surprised if predation happened occasionally, but out of all of the people who keep ghost shrimp in tanks with other animals, how many have problems?
