Nice trip report. Though you really neednt have bothered to use the thomas cook counter. Especially if you have airport transfer to your hotel already arranged, you dont need INR cash at that time of the night. Tip the driver a dollar bill if you want .. and change money in the city.

The other alternative - which I prefer - is to find one of the several ATMs you find around any major airport, stick your usual ATM card in and get cash in local currency. That'd actually give you a far better rate than airport foreign exchange counters. Anywhere in the world.

As for your rupees, get only as many of them as you actually need. And spend the rest of them by the time you get to the airport (or if you have small change - even INR 100 is around $2 US - keep it for the next trip).