You must visit Arunachal if you want to see what India really has in store for you. Having spent most of my life in India, and lived in the West, North, and South, I had a certain notion of what India is. I am not talking about food, language, religion, people, etc. I am literally talking about what India physically looks like. To me, India was a mix of flatlands, beaches, and some mountains.
NorthEast, specifically Arunachal Pradesh changed all of that for me. I will always remember those mountains, even if I never visit again. But I really hope I visit again, and again.