I found changing to green made the text far more pleasant to read if not actually easier ( somewhat a subjective thing I think )
There are now two dedicated Ethreads about HUD colour changing and a web page that allows you to dynamically test out different colour matrices.
Main HUD Colour thread is Here
HUD Colour Theme Editor thread is Here
Finally the HUD Colour Theme Editor webpage is here
It's not just subjective. Check out pentile oled displays and it makes sense. For every red and blue pixel there are two green ones.
This is the huge downside of these displays. They are used because they allow low persistence. Otherwise LCD with even distributed rgb pixels would be better.