I don't really have color specialized teams. Actually my primary team of Gorgotha, Emperor Khovash,, Sorcerer/Crescendo, Moloch is purposely built to have all 6 colors so that when I explode Gorgotha, I get maximum use of exploded gems.
For color focused teams, 2 color troops work really well. I have been testing a variation of the above team for Red Gem Day tomorrow of Carnex, Sorcerer/Crescendo, Crimson Bat, Moloch. My bat only has the first trait, but I don't expect it to ever have to do skull damage, so losing the 3rd trait here does not matter. I tested today a few red/green options to replace Crescendo, but I just like that too much. Also I am not running any brown, which is not normal for me to have a color hole.