We've just come back from 10 days in India with the following itinerary

Delhi: Oberoi New Delhi (1 night)
Varanasi: Nadesar Palace (1 night)
Agra: Oberoi Amarvillas (1 night)
Jaipur: Oberoi Rajvillas (2 nights)
Udaipur: Oberoi Udaivillas (2 nights)
Amritsar: Hyatt (1 night)

In terms of pace, we enjoy travelling at a fairly fast pace and the trip was a good pace for us but you might want to think about where you are spending your time - in my view Jaipur doesn't have that much to see so you might want to cut a night there. Agra and Varanasi can both be done in 24 hours each (although you will be busy) so you probably have enought time there.

We got a great deal on the Oberoi hotels through them as part of their "Summer Exotic Vacations" (we went at the end of September) so that slightly swayed our hotel choices in Delhi, Agra, Jaipur and Udaipur but the Oberoi Amarvillas was spectacular and without doubt the place to stay in Agra. The Udaivillas was also beautifully located and an amazing and very relaxing setting but I see your plans don't include Udaipur.

The Nadesar Palace is a beautiful luxury hotel and without doubt the best place to stay in Varanasi although I didn't think the food was quite as good as we had at Varanasi.

As stimpy says, we found Indian service was very attentive and well meaning but sometimes lacked the polish you might expect in other luxury hotels (e.g. ringing us 5 times in one hour with conflicting information about departure arrangements).