It is really impressive for a jam game! A proper UI is an essential part of a city builder, and yours is quite sleek. The tutorial is clean and makes it easy to understand all the mechanics in one go. The upgrades also feel very satisfying. While some background music could be nice, it's definitely not a huge deal for a jam game.
With these strong foundations, adding more content, and especially some unique challenges, could easily turn this into a commercial game. Excellent job!