I've noticed most of the vanities that have been implemented or suggested have always been around something being recolored or super shiny/sparkling/ and razzle-dazzling.
What about adding some more casual-like vanities?
I mean you've already added a few dresses and a tuxedo, some overalls. How about a casual "baseball" appearance-like hats or a school bag/purse back vanity? maybe even some basic black sunglasses for head-wear?

If you want to take these few things even further you can have 2 versions of the sunglasses, one where it is being worn/covering the eyes. and one where it is resting ontop of the head.