for a game about early medieval politics to imperialism in the later age, the addition of aboriginal tags seems rather odd considering the fact that the interesting nations to play weren't undiscovered ahistorical kingdoms, but centralized and active states that had differing goals and histories, and the tapestry of royal families competing with one another.
I would be more than happy playing other than European tags once in a while if both were fleshed out; different mechanics, different goals, different play styles, providing a different experience. Mesoamerican tags were such an attempt targeted by one of the earlier DLCs, and by then it was great. I actually enjoyed my Incan and Mayan campaigns even though the introduced mechanics were a little bit dull becauae very repetitive. That’s why I didn’t bother trying an Aztec campign, as I was actually waiting for some more tweaking... which never happened.
The federation mechanics of Native American tags too were cool, a solid ground you could build on... but nothing ever happened.
The introduction of trade companies was then the only new noteworthy mechanic to actually expand the game, not just inflate it with immersion by copy pasting all over the place.
None of African tags got the attention it deserves, and even had, e.g. in case of Ethiopia. Instead Ming got a mini-HRE v2.0, while the Shogun still has to deal just with a mini-HRE v1.0, buggy states got inflationary copy pasted, the technology is all messed up due to endless messing around with institutions, and, in general, all those click and get free stuff interactions got inflated too.
So yeah, I would be more than happy to try surviving as an Aboriginal tag if it meant trying out new play styles and mechanics, not just idling like a Siberian OPM or blitz westernising in the Philippines. Even as a coloniser having to fight off attacks of the natives could be fun... but that’s not happening either.