Although a lot of my work tends to be BDSM, because there is so much material to support that, I think one of the most erotic things is a slow striptease.
There are a lot of sets available with exposure or stylized "sexy" outfits but not as much in the way of removal of real-world clothing, either in a striptease, undress or changing clothes scenario. There are some good sets here for displacement or removal of clothes in couple situations, including school and office wear.
It's easy for someone with no ability at creating content to say, but what would be really good would be self-removal of multiple layers of clothing (outer and under wear). There's probably also scope for more couple / group straightforward removal of clothes from an unwilling participant, but that's catered for more by current exposure morphs.
Obvious targets would be uniforms - School, Cheerleader, Sports, Military, Police, Prison, etc. - but anything that might be worn in real life would be nice. From outfits worn by "innocent" characters, to stripper outfits and points between.
Maybe with talk of people buying less, it wouldn't be worthwhile, or it might be what inspires some people to buy more.
If anyone wants to point me to things I might have missed, that's fine. As I've said elsewhere, although I have G9 and G3 characters, my favorites are all G8