How about some kind of protogen character, if you make a fuckible character for the robot it could also be one of the variations when you use the prismatic apple. Oh, you also aught to update the description for the prismatic apple since is does more than change their color pallet now. There are also a lot of robot girls I think a lot of folks are into you could add. Maybe you get the robot guide after getting all of the girls or buying a bunch of stuff from the shop. Or, maybe you buy them from the shop for a hefty price.
Someone suggested something like this before, more locations on the map; what if once you get all the girls on the main island, a bridge opens up and you can go to a mini island or something to find more characters, or just have a boss fight for one more character.
Option to actually genderbend, instead of just turning them into passible for a man futa girls.
Already set optimal body type chooser so it's faster and easier to even out the pupations to look natural. Like, maybe a little techno screen from the robot helper can pop up and it's all green and digital looking, there could be slim, thick, and hefty just to keep it simple. The last option could be a customizable setting which you could save and chose to apply to any of the girls. I'd call it "Magic remote" or something alike. "Magic diel"?
Lastly, it would be great to have an option to turn down or turn off the visual effect for jizz flying out the entire time during sex, it's quite distracting and looks real off when the 'pump speed' is slow and there's a fire hose of jizz flying out the girl.