Just thinking aloud:
In that case, it may actually make sense to entirely replace the UI (i.e., the home screen) with a custom one. This isn't all too difficult. In the simplest (and maybe even best) case it would just display something like (imagine that this is a graphical screen):
< Book Title 1 >
Tap on ">" and you get
< Book Title 2 >
As long as you don't have hundreds of books on the device, this should be usable. And if all books are in the "good old" mobi format (not PDF or KF8), it would only leave your request A) to be figured out. And I'm sure that this is doable as well, somehow.
I'm hereby volunteering to support such a project, if you want me to.
Just out of curiosity: is this a personal request, or are you working for some kind of charity/hospital/other organization?