My visual acuity (last I checked, which was some time ago) is around 20/400. I also have nystagmus, which makes my eyes wiggle about sometimes and affects my focus, and strabismus, which prevents me from having stereoscopic vision (I can’t see 3D, such as in movies or on the 3DS). I can be light sensitive at times, but my big problem with light is that my eyes don’t adapt very quickly to new lighting environments.
The colored text is the biggest problem, but my eyes tend to get tuckered out pretty quick if I’m trying to read black on white, or dark-on-light, in general. I haven’t installed any new fonts, but I’ve tried Emerald, Ruby/Sapphire, and FireRed/LeafGreen. The size and shape of the text is fine for most of those. It’s almost entirely just the color.
As for the high contrast color scheme, it wouldn’t be much of a problem for me if the frame and background looked similar. Because of my vision, nearly everything for me is function over fashion. As long as I can read the text without needing a break after a few minutes, I’m more than happy.
For the Options menu, red text for selected options should be fine. However, one feature that could work really nicely is if selected options had a little white box around them on a black background.
As for other text in the game, I can’t quite say for sure, since I’ve just gotten to my starter Pokémon, so I don’t know a whole lot about the battle interface. I know that the Pokémon list page would be much gentler on my eyes if it was high-contrast, especially the Skills and EV/IV screen. As a rule, any time you can make it black background, white text, it will help. Always. I promise.
One more thing that I can ask for here (and it might exist already, but i should ask anyway, just in case) is for a font that uses bolder, cleaner lines, and doesn’t use the shadow effect. It was something I nearly overlooked until my girlfriend reminded me that I am, in fact, allowed to just ask for stuff that would be helpful, and not necessarily vital.
Anyway, I want to thank you for responding so quickly, readily, and enthusiastically. It makes me very happy when folks like you are eager to make the gaming world a more accessible place. 