Thanks for your feedback! I'm glad you liked our game!
We noticed that a few reviews pointed out the lack of upgrade consumption/production. This should be found by clicking on the buttons with "Lv. X". We're sorry that the tutorial did not explain it very well.
Initially, we wanted to keep everything on the same screen, but we were afraid that it would've turned out too crowded. We didn't think to let the player modify the scroll speed this time, but next time we'll certainly try to add it. A collapsible and scrollable side menu that lets the player select the building is also a wonderful solution to the problem! We'll definitely keep it in mind for future works. (☆^ー^☆)
Thanks again for the amazing feedback!