Depending on the city in Poland they might also be either painted in pastel colors or there might be murals on them.

Example:

And the wide green corridors between them were a constant feature as far as I know (at least I don’t remember NOT seeing wide grass + trees + some flowers corridors between 'em).

I do agree that Czechs picked better colors for it and keeps them fresher.

Yes - if you look at the PCR history you’ll notice that China pivoted hard to capitalism and extorting the proletariat in the late 80’s and 90’s, to the point where there were communist intellectuals and workers protesting against it - Tianmen Square protests were (also) against pivot from communism, see e.g. https://socialistworker.co.uk/news/china-1989-workers-in-revolt/

I’m from Poland.

I’m talking Soviet-style, grey concrete commieblocks

So the commieblocks are always:

• few minutes walk from school, kindergarten, grocery, doctor’s office, post, dentist and bus stops
• sane distance from another block
• either surrounded by good greenery, or next to a park
• surprisingly good quality
• small elevator
• little parking spaces

Vs “modern” blocks:

• large elevator
• the blocks are so close, if you open your window you could pee in the neighbours coffee cup
• usually surrounded by pavement, cement, or car parking
• better at noise reduction
• you’re more likely to need a car to go to doctor’s office or drop your kids off, or go to the grocer.

To me the ideal is the commie era urban planning with modern techniques, but that’s uncommon.