A very simple minecraft mod which allows users to disable the spawning on any minecraft entity. This will also remove all existing entities of a banned type from that world.
I can't reproduce this issue at all. I think it might be an issue with your config or perhaps another mod that you are using. Could also be bad luck with RNG.
for some weird reason bunnies and ghasts dont spawn naturally while using the mod even though all the spawns are turned on from them