When I initially looked into it, back in November, I didn't have much time, and it had been quite a while since I'd touched the relevant KOReader code.
I was in a hurry, and I mistakenly remembered the code as not modular enough.
Fast-forward to now, after I spent two weeks reworking that code for unrelated reasons, so I'm now once again quite familiar with it, and, yeah, not as bad as I initially thought
. Working on FBInk in the meantime, as well as seeing how Kobo handled the hardware update also helped
.