The more green you can see through your day scope is the key to seeing more of the standard black reticles. Using a IR illuminator helps immensely and does not wash out a black reticle as much as you think. In fact, (IMHO) I find the lighted red reticles show much less contrast (maybe my because of my slight color blindness which 60-70% males have).
Now with that said, one of the best colored reticles I find for a clip-on is the BLUE ones than can be special ordered through US Optics work amazingly well. We had them out here approx 3 months ago showing a few of their new line of day scopes and one of them had a blue lit reticle installed. They said a customer special ordered it and they did not know why...I know why! ;-) The blue is VERY relaxing on your eye and contrast extremely well with the green backgrounds and of course black.
Just my thoughts on lit reticles on what I see.
Vic