There are a lot many options-
Rishikesh, Dalhousie-Khajjiar , Mussoorie, Spiti valley, Coorg, Gokarna, Manali-Kasol-Tosh, Dharamshala, Mcleodganj, Chadar Trek, Beas Valley Trek, Roopkund Trek.
You need to decide whether you want to go to North, east, west, South as everywhere there are places Worth going to.
If you guys want to visit beachy place, you can surely explore the beautiful islands of Andaman in Nov, few beaches and islands are very seculed and beautiful. If you are planning North, then Himachal Pradesh would be the best option - Shimla, Khajjiar, Dharamshala, McLeod Ganj, Tosh, Manali are some beautiful places to be visited?? Happy vacays!