Could it be possible to add an option to "turn off" or disable zombies, murderers and scarecrows from fighting everything on the map?  My server is heavy-laden with zombie hordes and then add murderers and scarecrows who misbehave and attack my zombies, scientists, animals, each other.  I like that they are aggressive but can we make it so they won't attack other NPC's?  It's pure carnage on my server with NPC fights all over the map! LOL.

Yes, this is planned. I'm currently rewriting this plugin so it will likely be added when it releases.