For now, I omitted the password portion -- I want to include it, but because the total ROM space is going fast, I want to make sure I have the rest of the content first. So right now the subscreen looks a little weird, all bunched up at the top. I'll spread it out a bit if I decide not to do the password. And I need to adjust a few things (key colors, horizontal alignment of the keys, etc)
I'm also alternatively considering adding some sort of low-resolution map to the bottom half instead. I have no idea how that might actually work, or if I have any possible way of actually doing it with the limited resources I have. But it sounds cool.