This is a very nice chill (at least at the beginning). I really liked the simple art style and the music which fitted the game very well. The tutorial is also very well made. One thing I did not understand was, that you could connect cities together. I do not think it did something besides putting them in the same grid. Maybe you could entirely prevent it. At the beginning the game is very slow and maybe even a bit boring, but then suddenly it gets very hectic (at least the way I played it) and hardly manageable. So maybe you could increase the difficulty / speed at the beginning a bit and lower it later (ramp it up slowly).
Anyway a very well made game and congrats to this nice entry! Had fun playing it.