Dravidians as an umbrella to be split is a sound idea from a historical perspective. There could at least be 4 new civs sinhala, Tamil, telugu, Kannada and kalingas. Tamils could be the renamed Dravidians. But looking at their tech tree. It would be a complete disaster without knights or cav archers. Those civs would need at least one unit for better mobility and civ specific overpowered economic or defensive bonuses similar to suggestion like this