If you would allow users to select their own colors for deleted and inserted text, as in diff view, you would help something like 1 in 20 Caucasian males.

Failing that, given how common red-green color deficient vision is, could you replace the current pale red and pale green? Given the prevalence of red-green "color-blind" people, it ought not to be too hard to find someone to guide you on testing improved reds and greens.