I've always found this to be the best order to do things in;
Start with the centaur, use her key to open up Pleasure Pastures.
Then Monarch, use her key to open up Virgin Breaks.
Then Matriarch, use her key to open Hivelands.
Then Queen Bee, use her key to open Climax Peak
Then Autumn, but keep her key until later.
Then Apopha Fesssi, use her key and Autumn's to unlock the way to Esoteric glade which also lets you hit the switch and get to the orcs.
This way lets you "quickly" unlock each area without making Mega Slime cry, allowing you to get the pearl and then the girl. After that, do as and what you please when you please. Anyone who hates grinding, just cheat - I haven't wasted my time on any version with trait/world levels, not when there are human sized slinky goblins with massive knockers to breed into existence!
Speaking of doing, can someone tell me how to break Pride so I can do her?!