As a basic thumb rule a good approach is to add a border to all shapes and play with contrast, so everyone can enjoy the graphics.
But I'm curious: Do you find awful to look at red-green combinations or does that make it hard to look at the screen? (besides not seeing the difference between the two). I think that's a good thing to know when making graphics, because you never know who is going to watch your creations, so I'd like to know if there's something beyond the basic color blind concept.