While we're on the subject of psychedelic Vincent Price films, your challenge is one of my favorites from Roger Corman and Edgar Allen Poe.
Masque of the Red Death!
The same challenges that you gave me apply as well. Watch the film from a design point of view with color costume, and wacky 60's hair. Also, try spotting some other Edgar Allen Poe references in the film other than the story its based on as well as how this story was adapted to a full feature film. If you haven't seen this one...which I bet you have because I know you touch yourself to Vincent Price, I'm sure you'll love it!