"I think if you work on some of the strengths of having a start-up in India but with global reach and applications ..." - Can you please elaborate on these strengths of having a start-up in India (apart from lower costs of living)?
I could go on.
I guess at the end of the day it all depends on the problem you are looking to solve or the "big idea". For e.g. If your startup is about making it easier for suburban residents to interact with their neighbors or promote neighborhood activities - Mumbai would be the wrong place to start that startup. But if you are looking at implementing infrastructure technologies for dense urban setups than Napa Valley, CA wouldn't be ideal.