So combat priorities can't be fixed? Or do you think some iteration of Neutral players would result in the enemy Neutrals not focusing players? I've noticed Neutral Extra behaves very normally. They attack players exactly how they should. I just need another Neutral player that behaves like this.
edit: After reading that thread, it looks like you can make Neutral Player Units ignore the script that makes them go back to where they were created, which is nice. I can change the Gameplay Constant so that units don't agro across the entire map. It doesn't fix my issue with target preference being strictly to player units though.