I can fantasize enemies dropping Power-Ups (damage/attack speed/health/ammo/ovulation potion(/consumable/egg)/birth control items/invincibility/invisibility) or straight up money and then add vending/gacha machines that sell such power-ups. Put vending machines at savepoints, have several power-up consumable slots you can bring with you, play gacha and equip as you desire. Also add Fallout-looking robot you can sell your babies to - go out > get knocked up > return > extract babies > big payday. Maybe make it into like optional "Arcade mode", for people who prefer enjoying games differently.
Nest of dominator
iirc has enemies drop boxes with "lootwheels" in them for example.