Well, I am a cosplay and dress-up fan, so I definitely have opinions on the matter. I really like a few Marvel and even DC (ugh) costumes. I love Black Cat, Catwoman, and Harley Quinn, but those may be too slutty for a party.
Check out Yaya Han’s portfolio on her website; you will get a million ideas. She is a cosplay legend.
I also love Velma and Daphne from Scooby Doo, especially Velma, which is more casual but a classic throwback that nobody else will likely be at a party. It’s sexy, but classic too. Plus, should hubby want to dress up, he can be Fred Jones or Shaggy.
If you want to be a bit cultured, Sailor Moon is hot, and you can have a more conservative top for a party that covers the stomach and something slutty underneath for the Mr when you get home.