Upgrades are harder to get on CO than on BA, I think. The good news is that you can wait-list for the upgrade and if the seat opens up eventually you should get it.

That being said, the upgrade costs miles plus cash, depending on what the fare you pay for the seat is. Also, it takes a lot of miles for the upgrade, generally 40,000 each way. And if you only accrue via credit card transactions on the SPG card you actually need to accrue 160K points for upgrades r/t as SPG points transfer to CO at a 2:1 rate rather than 1:1 (I'm ignoring the 5K bonus because I'm not sure how it plays, but the 2:1 bit is still a significant issue for CO earning from the SPG card).

The $375 card is basically a normal CO card plus a presidents club pass. If you are only traveling on CO on the India flights and are going to be in BusinessFirst then there is no reason to get the Presidential Plus card. There is a basic card that gets you the same points earning for your spending for only ~$85/year.