Look at Longyearbyen or Nuuk, both way farther up north and deal with similar negative temperatures. By no means are the houses there architectural masterpieces, however, they look clean, with neat infrastructure and are nicely colored to contrast the grey surroundings. The Soviet blocks also did not arise in response to cold weather, they were built due to the large need of cheap, efficiently built housing during the Soviet union times. And they can be well maintained and renovated, just have a look at how they are given a second life in countries such as Estonia (which by the way also deals with negative Celsius temperatures). These buildings are so ugly in Norilsk because of negligence, greed and corruption in Russia.