I live in PHX and just went through this process in figuring out routings to Bangalore. West Coasters do have the option to go West instead of East as it is exactly equidistant. I tried to find an all east, round the world option but nobody seemed to want to book that way.
*A seems to have given up all their trans-cons to Lufthansa. UA, US, CO all seemed to route to LHT 747s to Frankfurt, FRA-BLR with a 12:15 AM arrival. Beware, my reading on LHT 747s is that coach is just about the worst of anyone (pitch, no IFE, etc), however that's how my ticket played out.
Another option is British Airways to Heathrow (LHR) to BLR.
For the western route, I believe you would do Cathay through HKG and SIN to BLR. It's a long-a$$ route though in flying time at 30+ hours. The perk is coming home you get to arrive prior to your departure "Superman Style" thanks to the International Dateline.
Can't give much opinion on Chennai.
On the upside, if you were doing a paid ticket, you would be earning 22k miles on one Round Trip.... nearly elite status with any carrier.