Nepal is an excellent country to visit. Some may say it is a soft option compared to India but I'd disagree. Nepal has some of the finsest scenery around. Add in friendly people and more or less the "right" amount of tourists/touts (except for Thamel, Kathmandu) and you have everything to offer the trekker/nature enthusiast.
The highlight of my stay in Nepal was the Annapurna trek. So full of highs and lows. The highs were the wonderful scenery, being with a great group and meeting lots of interesting people on the way. The low was my AMS (obviously).
I would definitely go back to Nepal again, to finish the Annapurna Circuit, see more of Chitwan and to see the World Elephant Polo Championships that I missed by a few days!