Cocijoeza was a historical figure during the time of the Huey Tlatoani Ahuizotl. As ruler of the Zapotec kingdom of Zaachila, he initially lost Mitla and Hueyxacac (both were sacked), yet managed to recover control of both cities while the aztec forces continued onwards unto the Soconusco, and forced Ahuizotl into a stalemate at the seige of Guiengola.
A secondary potential hero is Zaachila I (founder of the Zaachila Dynasty) or Cosiiopii/Zaachila III (who expanded the frontiers of his kingdom greatly, and attempted but failed to reconquer Monte Alban from the Mixtecs). One of these, likely the latter, had a legendary rivalry with the now borderline mythical mixe King Konkoy (Condoy), part of a series of longstanding confrontations between the two peoples.
I believe we know a few Zapotec Kings of the Monte Alban heydays, but it's probably best to go with postclassic zapotecs and include them with the general Mesoamerican mod.
Regarding accuracy, I'm afraid their are actually quite a few flaws, both in units and architecture that I took notice of. I'd suggest (if possible) to replace the models of a lot of those structures, and have pictures of examples that would be useful, with possible variants in accordance to levels and just variety for the sake of variety. This includes such things as defensive walls, central palaces, market place, etc. I'd also have a couple of unit suggestions, though I wonder what other mesoamerican faction are you thinking of including?
The Mixtecs share quite a lot of history with the zapotecs and might justifiably be included within the same faction, though just as easily could be a similar rival faction akin Athens vs Sparta.