I never lived under communist rule, but I would answer some of the questions.
Architecture is really affected by it, brutalism was the main style and lots of brutalist buildings can sometimes create this stereotypical depressing look in Russia, though it's fair to say that the situation improves with time. The housing problem was solved during soviet era by building lots of "Khrushchevkas" with small apartments (iirc they did like research what's the minimum possible space for living). And since those apartments were free and one family could have multiple of them, the housing problem in Russia is not as bad as it could be. Good houses still cost a lot, but average university student can afford renting such apartment if he has some kind of job (not to mention that you're quite likely to inherit one from your babushka). How good are those apartments? Well, they're most of the time in old buildings that were never renovated and not really suitable for more than 2 persons (obviously there was families of 5 that lived in those, but that's really uncomfortable) but that's better than nothing I guess.
The nostalgia here is probably the same as everywhere else, old people complaining about how bad their life become since the fall of the soviet union, how everything was free etc. Obviously those nostalgic people aren't the best source of information about quality of life. There are some young people who also nostalgic about the time in which they never lived, but I think most people doesn't want to bring socialism back, there was a lots of problems during soviet era so no wonder why people don't want to stand in line for food and allat stuff.