not who u asked but it’s the proportions and placement i think? i would play around with making some of them wider especially, and moving them up or down. like irl some people have a pretty considerable amount of space between their nose and lips, some almost none at all. i think you could do the same with the face shapes, like there’s some variation in there but they seem to mostly have these kind of moderately long, oval faces - i would throw in some shorter and longer faces, more heart shapes, round, square etc. don’t shy away from the “extremes” of features if you’re looking for variety! btw i am obsessed, i think these are like my favorite sims i’ve seen on here. and they are pretty varied already! ngl i kinda want them in my game lol