Tweaking the original idea (which I took to be all in good fun, although on more sober reflection, maybe the idea is just fitting for isolated instances of people who really have just recently graduated), and in the spirit of Jon Jacob's meet-up idea for newbies, would anyone planning to hit the First Night want to meet up before, during, or after? Maybe this can be combined with JJ's group. Just a thought.
In that case by all means wear what you want, but please don't expect anybody else to go along with this idea. When I was an arena season-ticket holder (for the best part of a decade in the 1970s) I loved the music, night after night, and detested the so-called "traditions". Those haven't improved - there will always be overgrown schoolboys wanting to have their idea of fun. Someone else described this proposal as cringe-inducing and I have to say that I agree with that. But you were only a making a suggestion - which is fair enough, of course.
So - back to what matters. I am certainly looking forward to tomorrow night's concert.