I like emotional h/c but only if it's really very... dialled up to 11? Like, I'm not massively into reading gentle comfort about someone having a distressing day, but calming someone down after a panic attack or someone being completely in shock from a traumatic event are GREAT. I mean, in general I'm mainly into dramatic, genuinely life-threatening h/c much more than any other sort, I'm just not a very restrained person in fiction!

All the other things on your list, absolutely! :D You are so right about altitude sickness, I don't think I've seen it done in a fic either but it has so much great potential.

And yes to concussions being a favourite. Headaches are my least favourite things in real life, I don't really know why they're so endlessly fun to read about in fic! And of course the confused/blurry aspect of it is always wonderful. (I just tried to think of how many concussion fics I have written in my fannish life. I don't think I'm remembering all of them. It's A Lot XD)