No comment on the rest, just wanted to say I was thrown off by the "South Asian" thing too. Not tip-toeing around calling Greece "Southwest Europe."

South Asian is reasonably common in UK.

It avoids having to include Pakistan in India which if you did causes a large number of people to complain especially if talking about modern things. It is less usual when talking about ancient history.

It also differentiates Indian sub continent for East Asian which covers Chinese, Japanese and Korean. Asian usually covers too much when talking about history.