If ya making some potions, I love some size-altering ones, curves included would be nice. Either temp or (for harder to craft variety), that can be used both for lewd play, satisfying certain monsters, and the occasional puzzle. Same could apply to other ablities and the sort but gonna call out this one if ya feel like adding it.
And gobbo. (optionally being sat on).
Wish ya luck and see what else ya come up with.