Can you help me to plan for India and RTW?

I am planning on taking 4-5 months out to travel with my partner. We're hoping to go to Thailand, Laos, Cambodia, Vietnam, then on to Australia where we both have relatives. We'll probably spend a month or more there and will also go to Tasmania. Following that we'd like to spend time in New Zealand and travel on to Sth. America - Chile, Peru, Argentina and Brazil.

However, as our schedules haven't allowed us to depart at the same time, I would like to go ahead at the end of August or beginning of September and he will probably be able to join me from mid October onwards. In light of this, I am thinking of spending some time in Kerala in Sth. India. Ideally I would like to spend a couple of weeks chilling out but I'd also like to do some courses or some yoga. I'm interested in holisitic medicine and would love to learn more about the Ayurvedic treatments.

Can anyone advise on the itinerary above especially with regard to Kerala? Is there anywhere you'd recommend that would be safe for a woman on her own to spend a month or so? Any where that would be good to take some courses?

Any and all suggestions are much appreciated! Thank you.