Ask questions, meet dancers, and be part of the conversation.
I watched a rather LARGE feather headpiece on a pro at Blackpool 2012. I thought, personally, it was distracting from the beauty of the lines. Although, if you don't try you'll never know. If it is part of the total package and doesn't distract from the neck, posture, lines, etc...then at least try it. Word of warning, try it in rehearsal as well and see if there are any issues first that need to be fixed....like staying on the head, hitting the feathers, etc etc.
IMO it looks like something that would be more at home at a Roaring Twenties costume party than a ballroom comp.