Well, I didn't want to use Blood as it's not thematic in this case. And after all, if I want Blood, I could play EA!

So Tlaloques are, in my opinion, not very thematic for this era, too. BTW I used Lawgiver for Pretender - after all, it's about him! But his worth I cannot divine...

Jade Serpents I tried to use as banners for Giant Toads, but they just ran forward and got slaughtered.

Against elephant rush, though, they may be worth it...
And yes, I usually try to get at least some Earth bless if I have sacred mages.
Communion potential - yes, probably. But on the other hand, we have many nations with it... Many flying mages, however... yes, it may be their unique feature.
Thanks in any case.