Yet another fork of Android?
Just fork the base, add in region specific bits & bobs, give it a local theme, and call it a day.
You would need to create an India-specific PlayStore alternative, but you've got the potential developer & customer numbers to make such an endeavor a viable option.
Best of all, if you can use the government to back the project to launch that sucker (rather than letting it grow/fail naturally), then you could make something non-Indians might want to buy, too.
Imagine what could happen if you made a better version of Android than Google & beat them at their own game!