I sometimes used egg-white when I had a mohawk, but that was before I started aikido (and even then I usually left it down). I imagine 15 minutes of ukemi would have ruined it anyway - hardened egg-white doesn't bend too well. A friend of mine (who also does aikido, and also used to hang out in the local punk scene) tried just about everything she could think of in the past (tip: certain kinds of industrial soap are just perfect, but _not_ when it's raining outside
).
She now has a normal hairstyle (and life), and I've shaved everything off some years ago. It's so much more practical - only now I sometimes get mistaken for a nazi skinhead outside our dojo (usually by the same people who gave/would give me the evil eye for being a "punk", so I don't really take it very seriously). *shrug*
One of our members had a mohawk at one time, so I know for a fact that sensei doesn't really mind (though it was shorter than yours, and not colored). This guy did say it bothered him a bit when he was doing backward rolls; he eventually shaved it off.