I did not touch or mess with any settings for Gleba, but upon arrival, every egg raft except for 2 near the starting area were guarded by like 10 stompers and 10 striders, all piled on top of eachother. It's basically impossible for me to even get setup on Gleba right now because of this.
EDIT: After discovering new chunks on Gleba, I watched it with my own eyes. The egg rafts start with nothing around them then just start spawning stompers and striders constantly. They are taking the spawnrate change from the zombies.