Color blind option variety for the website, and all apps (including phone, console, etc.) I have Achromatopsia and it would a big benefit for other possible users to have something that does not blend everything together.

Achromatopsia is colorblindness to the extreme, no color, basically what others would call grey scale eye sight, I have it, and a lot of websites including Twitch make it hard to navigate with some things that blend together. I have problems with the purple and other colors clashing causing me to either not see words, or other things.