"The city is not small, but big."
Translation:A város nem kicsi, hanem nagy.
Quick rule is that you can only "front-load" kis, so you can say "a kis város" (a small city), but not "*a város kis".
I'd say yes. (native speaker) A quick google search also implies that it is.
It actually can, the only difference it makes is that the sentence will focus more on the "smallness" of the city rather than the city itself.
A város nem kicsi, hanem nagy. = THE CITY is not small, but big. Nem kicsi a város, hanem nagy. = The city is NOT SMALL, but big.
We tend to put what we're focusing on in a sentence to the beginning of it.