Probably already come up, but I find the 2 major waist attahment points being split between skirts, belts, nethers, and tails makes it sometimes difficult to juggle a female tailed av. a tail attach would go far in alleviating this annoyance.
Another annoyance I've found is a lack of "tattoo" overlay layer between the skin and underwear set, which makes layering clothing sometimes harder than it needs to be when one has a tattoo and can't find a suitable pants layer underwear, but has tons for the underwear layer
Not really gamebreaking annoyances, i just think it would be really cool if those existed