a hyper chemical that makes the effects go to unrealistic extremes when combined with other chemicals in the chemical manufacturing table. like if you combine geyserex with the chemical you unleash torrents of semen rather than a normal amount or a canfull

if you reach orgasm and your cum hits one of the pre-generated scientist npcs they'll react with disgust (or lust)

if you manage to reach orgasm while wearing pants, cum stains the groin area and continues to stream down the pants until falling out of the legs and onto the floor

Ear penetration and cum in ear (anatomically incorrect). No gore involved. 

Male general constitution, female genitalia.

Being able to fuck breasts *literally* would be cool.

i guess i do have a bit of a diaper fetish but not extremely. but it would be cool if there was diapers or peeing in the game and to be able to use toys like a vibrator with or in the diaper to make the the subject cum or pee in the diaper. but if not the diaper at least the peeing\wetting will be good.