I notice a lining of arrogance in both your answer and OP.
Here’s some constructive criticism.
You can’t make a scientific model by which decide the most deserving civs to be added, for a couple of reasons (at least).
- There’s no unit of measure for that and you didn’t provide one. You just commented a bunch of maps reporting names, territorial extension and ethnicity in a certain timeframe. By that, your ranking is arbitrary. You’d have to define a universally accepted unit of measure but good luck with that.
- The Devs can’t use that anyway because they have other factors to consider.
There’s no strong link between your conclusions and the data you provided. It’s not clear how the arguments provided support your thesis. You have to specify what interpretation of the data leads to your conclusion, you didn’t do that.
When you have a proposal, be humble. Nothing any of us write can be sold as a definitive, game-changing, do-or-die solution. You aren’t entitled to command anything to the Devs.
You have a partial opinion on the Persians. That collides with a fact-based proposal, it’s inconvenient. This whole topic reads like a surreptitious way to have them added ASAP.
Considering all of the above, your post is too biased to be taken seriously, despite your claims for an indisputable solution to the grievous problem of the variants. So, you should try to edit it and make it better.
Now a spot on comment about the civs you proposed.
Incas, Majapahit, Spain are seemingly good proposals, nothing to say really about them.
Mamluks seem lower priority than other civs, more for the already present Abbasids and soon to be added Ayyubids variant.
Cholas could be a candidate, though in other threads other good proposals have been made. The Indian civilizations issue though applies to the Persians as well. In the middle ages, none of them had a single, enduring state/kingdom/empire by which represent the civilization. It’s inconsistent to advance a specific empire for the Indians and a generic one for the Persians.
About the Vikings, you fall short of what you originally intended, calling them Vikings and not Danes. AoE4, more than AoE2, tries to be specific about the Empires represented.
To end, a worry.
You make names and point out what you call major empires. What if somebody proposes a name outside that list?