well if you have interest in exploring Nature, than Ranthambore is the place you would not like to miss if you're in Rajasthan, trust me if you're traveling so far than do watch out for something which you wouldn't like to regret once you have returned from your trip.
Completely off the subject however what are your plan for Holi? I have met a few people off other websites and have created a group for us all to talk and get to no each other before we meet up. All of us will be there before and after Holi, were all planning to be up North as apparently its best there.
Give me a shout if you want more info