So my first appointment with a therapist to start determining my options re hrt, androgyny and mechanical augmentation (because who doesn't want a drill for a hand?) is <24 hours away.

I'm terrified. Not because of any significance of the event, but because I'm cursed with a penchant for hyperbole, sarcasm and irony that combined with my 'make everything ridiculous' defense mechanism makes the first words out of my mouth the most likely to get me a swift boot out the door. My assumption is that "The word cannibalism is thrown around so much lately... Wait, are you my court appointed doctor?" will not break the ice like I would hope.

So, any experiences or advice?

Don't worry about breaking the ice.  Just be yourself and be open with your doctor.  You're going so they can help you through your situation. The best way for them to do this is for you them to get to know you on a personal level.  That means getting to know your quirks and idiosyncrasies as well; although, I would probably not mention cannibalism unless it's relevant.  I'm hoping for everyone's sake that it's not 

You'll have a great time and will feel so much better once you go through with it.  It's not as scary as it seems.  Good luck!