On the same vein of how people interpret classes, I personally think that the rage class is probably a good one to link with '(Hidden) Truth' and the blood aspect to be able to symbolize familial bonds, especially without how bloodlines are and such.

I can definitely see Blood tying in with Family Bonds for sure. As for Rage and Hidden Truths, well the Canon Aspect Description does say, and I quote:

They posses great contempt for lies or false ideas, including the stability that false ideas can impart. To them, the true is far more important than the good; they would tear down a system just to destabilize it if, by their reckoning, it is built on faulty premises.

So the concept of the “Hidden Truth” would fit that description. That may be a bit an overlap.