I've said it before, but I just don't think they look very compassionate. With the other Corps, the creative teams have done a pretty good job of designing members that suit the emotion they represent,
I might argue that point, given that all the characters look like their emotion when viewed from a HUMAN perspective. We associate fangs and claws with the negative emotions like rage and fear, but why assume that's the norm? Tigorr of the Omega Men probably views that as "Oo-err check out the fangs on HER! Hubba hubba!". At least the Indigo, like the Green, seem to be made up of a vast array of forms and not all are human norms.
But then again, I still think the whole emotional spectrum notion is a nonsense, since we're defining emotions (which I still say willpower isn't but lets not start that again) by the precise spectrum visible to humans... it's not even the majority spectrum for EARTH inhabitants (insects tend not to see red, but do see further into the ultra violet than we do, and they outnumber humans by millions to one)