Hey YT,
I am definitely one of the older guys around here, but let me just say that you a fretting too much. Just go ahead and shave the dome. Now is as good as time as any, but you can certainly wait until you begin your trip if you want to. (It sounds like a great adventure, btw.) When you travel people will accept you as who you are...it may take a few days for you to make actually-being-bald part of your identity; but once you do man you are going to love it.