As a side note (addon)... I use 36 Red, 98 Green, and 225 Blue. That is a (to me) pleasant color that contrast with all the major race colors. I checked in Paint.
I've been using 127 green/127 blue myself. It's a nice turquoise/teal that is dark enough that it is easily distinct from the Altarians, and no other race comes close to the spectrum. Furthermore, it's light enough to see.
I've tried many different blues a number of times, but I always run into issues with the Terrans that way. You seem to have found a blue that doesn't interfere with the Terrans, though my pseudo-OCD has an issue with the numbers. I'm sure you can guess why. 63 red 63 green 255 blue achieves approximately the same color, albeit a little brighter (which is hardly a bad thing, is it?) And in fact the red is hardly necessary, but I suppose that's a matter of preference.
I've been messing around again and I think I might try 127 green/255 blue. It's kind of light...almost -too- light...but it looks good.