Would it be better to paint the full rear sight plate one color and the front ramp sight the normal way? Would that allow the rear plate to give you better focus on the front as the rear may fully disappear into the back ground instead of blurring a bit into the front? Bluuring may happen in the middle of the night with just woken up eyes and poor lighting.
I know this is a stale thread but I was hoping someone might know.
That's an interesting thought, and I have seen commercial sights setup with the rears a different color than the fronts. If you use nail polish (cheap, and at the corner drug store/supermarket), you can also just buy a little nail polish remover too - I'd suggest getting two colors and experimenting. Cheap nail polish is only $2-$3 per bottle.
The best I have found is engine paint. You can buy a can of it from a local auto part store.
It's oil resistant, heat resistant, comes in many colors, will almost never wear off, won't crack peel or any of that stuff, and unaffected by solvents you use to clean your gun with.