I like Prom too! I brought up 70's/ 80's, that wasn't met with much enthusiasm, I like the idea though.
It's a fundraiser. Not sure how many people -- probably 50-100 range.
Venue hasn't been ID'ed but previous events have been in hotel ballrooms/ conference room type places.
I'm currently loving the Mardi Gras idea -- this year it's February 24th, that'd be around the right time (no date set yet). I think the main issue there would be to find out if there is already a competing event set for that. If not, that's a front-runner I think (we could even provide a stack of masks as necessary). (Oooh, deaf party though, I wonder if that'd be a problem? Harder to communicate in masks, both in terms of seeing out and seeing expressions/ grammar.)