Hi Wanda,
I would say that when you are travelling long distance it’s cheaper to use flight e.g. if you want to come to Bangalore from Delhi then I would suggest a flight. A flight one way would take 2 hours odd and 3500 INR (approx) whereas it will take more than 24 hours by train. The fare can be cheaper depending on how would you like to travel but if you consider the time factor then flight in this case is cheaper.
Hopping from place to another place in nearby areas again is much better if you take a bus. It will give you a chance to see the places from close quarters, meet local people and taste the food.
You can make Delhi in north, Bangalore in south and Calcutta in east as the base and then go around the places. From Delhi you can go to Agra , Jaipur etc and from Bangalore you can cover Mysore , Ooty etc.
Mysore is just two hours from Bangalore.
Ooty takes 6-7 hours by bus from Bangalore and 5 hours from Mysore. A direct ticket would cost you around 400-500 INR (based on the type you want to opt for. It can be cheaper as well). On your way to Ooty, you can stay for a day in one of the National Forests as well. It’s an amazing experience. You can also go to Kerela.
I personally would like to suggest Coorg as well which is (maximum) 6 hours from Bangalore.
Depending upon the places you mentioned I think you can start from Delhi, then Jaipur & Agra etc then Goa and from there to Bangalore.
I don’t know what kind of places you are looking for. If you can let me know about the places you have in your must-see list and also the kind of travel that interests you, perhaps I can help to work it out for you. Eg now-a-days I love to travel to off-beat places. More solitary it is and far away from shopping frenzy tourist mobs better it is for me. Anyways, let me know if you need any help. I am going to be in Bangalore if I am not travelling.
Feel free to shoot questions.
Cheers,
Reshmi