here is a request, a ghast. HA! unless you want to that is just a joke. Here are a few cool idea's in my opinion.
A diamond ghast. This ghast looks like a diamond ore. The player says"yes diamond then goes to mine it" *boom*
A obsidian ghast. They have tons of hp and drop obsidian.
A tnt ghast. They throw tnt at you when you come close.
anyway your mods are awsome good sir, keep up the good work!