If you want to feel the nature and peace then go to some offbeat places in uttrakhand of Himachal Pradesh as well.
Here are some offbeat places'names - Almora
kausani
kanatal
munshiyari
Lansdowne
tithan
chitkul
etc....
suggestion - prefer homestay rather than hotel.
If you are planning north of India Srinagar Pahalgam Leh Ladakh
Shimla manali Lucknow Chandigarh Nainital mussorie Mcleodganj Chopta Dehradun Lansdowne are some ideal spots to travel now. East India here are some spots
Chennai
Madurai
Pachmarhi Pondicherry Kanyakumari
Araku valley Kanha national park Vizag
Hyderabad Lambasinghi If you have asked for north east India here are some spots
Meghalaya
Sikkim
Darjeeling Mawllyngnong
Nagaland Majuli island Mokokchung
Nohkalikai falls Khawnglung sanctuary Loktak lake.
Does that 4 days include your travel time also from Bangalore? In that case, if you want to do north, stick to the Delhi-Agra-Fathehpur Sikri. For East, you can do Kolkata and Puri (Orissa) Or Delhi and Lucknow If you have already done Delhi, then do Jaipur-Ajmer-Pushkar or Jodhpur and Jaisalmer
U can also visit North Bengal, Sikkim,Its beautiful.. Check out Some images on my profile.. If u need any information about the place I will guide you.. Its in budget also, For 4 days trip its good option..