There is not a single society that exists out there that does have problem. We are humans being, we are born to solve problems till the day we die. So even if you do solve the above mentioned problems today there will be more in the days to come. If we are perfect then we will be God, bhagabaan, yahweh, or superman(whatever you believe in).

As far as the Newari culture being extinct, he he WHO IS TO BLAME ? THE NEWARS THEMSELVES NOT OTHERS. All the foundations of Newari culture is still there but are not being implemented like it used to be. Thanks to modernization not just newars but other cultures are also eroding(sherpa, lama, tharu, gurung etc etc) thanks to implementation of Nepali Language and culture. But if we did not do that that Nepal as a country would cease to exist. Then we will be back to that same old feudal lil cities before the SHAHS. I mean they did what they needed to do to make Nepal a functional country by implementing Nepali Language and culture. BUT ITS UP TO NEWARS TO PRESERVE THEIR OWN HERITAGE.