The problem with Nepal is that the politicians who are supposed to make and uphold laws are busy filling their own pockets so noone really cares about anything. You could get a US citizenship and keep property in Nepal since noone bothers checking if you are still a Nepali citizen or not. If you have Nepali nagarikta then that's all you need.

This is the age when you ask not what you can give to the country but ask what a country can give you to. My advice is take the citizenship asap. Having US citizenship makes like a lot easier, you won't have to worry about being in status and filling in paperwork after paperwork anymore.