strong bladder - doesn't need to go as much - -2 metabolic efficiency +1 complexity
weak bladder - the opposite of strong - +1 metabolic efficiency +1 complexity
sweat less - there hygiene level doesn't decrease as much - -2 metabolic efficiency +1 complexity
temple like body - combines sweat less and strong bladder and maybe another one I've yet to think of - -4 metabolic efficiency +2 complexity

for both the new babies of biotech and colonists off colony
a special clothing to help them also i think its weird that the babies use bedpans or get mood debuffs because they can walk to the nearest bathroom.
also add a literal porta potty so its easy to have a bathroom for a caravan or new colony