Hi p_s_2,

I went thru this thread today and see most of ur queries are replied or u have been given detailed replies and advises..
My two cents..

1. Ur itinerary has all full service carriers and AFAIK, all these hv interline agreements which means that ur luggage will be checked in to your final destination which is BOM in this case ..
2. it seems your main concern is delayed baggage, then maybe it will be a good idea to take travel insurance which will hv some kinda delayed compensation which will take care of the intervening period @:-)
3. it may be difficult for u to buy directly from the airline with the itinerary u published, as u hv different airlines.. I would try sites and am sure you may get reasonable fares from BOM - JFK from other airlines( on only their carriers) at lil higher prices..am sure u must hv checked, but try some options and u will get something, also try from ur end point in India, since maybe the site will give u an alternative from another intl airport ( say chennai, hyderabad etc) which may be less crowded..@:-)

keep us updated.

cheers
Abhi