Break up India into at least broad representing the major groupings of highly distinct cultures that have existed since time immemorial in the region, and that all at one time or another formed an empire controling large part of the region - but rarely if ever kept it. In cultural terms, presenting India as a single culture or single civilization is like lumping Rome, France and Germany into one single European civilization on the ground of "well, they all conquered most of Europe" at some point.
These major grouping would include at least the northwestern Turko-Persianized cultures found around Pakistan, Afghanistan, and northwestern India (such as the Delhi and Mughal states); the North-Central and Eastern Hindi-speaking cultures of the Gangetic plain (including most notably all the Magadhan Empires - Maurya), and the Dravidian language family cultures of the more tropical and naval-oriented Southern India (such as the Chola Empire). Further subdivisions could be imagined, but recognizing the major distinction between these three culture groups is the first and most important step of breaking down India.
Thank you, never heard of the Chola Empire/Dynasty. Fascinating reading.
But I wouldn't count major ethno-linguistic groups as a Civ, Civ as a series never has, there's no "Pan Slavic" Civ just as one opposing example of bringing a "Civ" together rather than splitting it apart. Besides, the temptation to split peoples cleanly into ethno-linguistic traditions seems a poor one from a historical research perspective. Someone in the US today could've had parents from Mexico, grown up eating home made tacos, and still never been to Mexico nor speak a word of Spanish. The real world of today is much messier than some sort of clean lines between distinct groups, and thanks to the major breakthroughs in archaeological DNA recovery we know the ancient world wasn't hugely different, someone from northern Europe could show up and die as a mercenary on the island of Sicily thousands of years ago.
Division of people into distinct ethno lingusitic traditions is one I've witnessed as driven by current day politics and may as well be supersticious beliefs, as it doesn't match up with history or even the current day. Just witness the ludicrous tale of Kosovo, a place that I've seen natives born there in the 80's and earlier say was a relatively calm place despite what attempts at dramatic histories might portray. The "division" between Albanians and Serbs was mostly ignored by the vast majority of the population, until the troubles really started in that direction. Not of course that one could actually make any DNA distinction between Serb and Albanian as such, or cultural distinction between peoples that had been intermixed neighbors since forever. But politicians started using propaganda to paint "In" and "Out" groups, Serbians and Albanians, ramping up violent rhetoric more and more until the whole place burned down over imaginary differences. Civ as as series certainly does not need to support any such notions, or anything even close to adjacent.
Instead the current tradition of Civ just having a "distinct" historically recorded significant political structure, rather than anything else, seems a much cleaner and easier to use definition.
Even then one can split too much. Chola would be neat. But I'm not sure I'd count Chola as India, or breaking up India, it's the southern fringe of current India and a large part of the Indian Ocean. And since Mauryan and Mughal Empires and Current India line up geographically "well enough", more than well enough so far as I'm concerned, I still don't see an argument for "breaking it up". Seems to me may as well call for separating England, Scotland, Wales, and the British Empire into separate civs each. One can get a bit carried away EG: Texas as a seperate Civ from America, it even had it's own official embassy in London, surely Texas should be separate right?