Great game! I love the art and the UI is indeed very clean. I understand the repair might be very handy, but I would appreciate if when you click on an upgrade (buy slot/repair/deconstruct) the action would remain saved until you right click or run out of money. It feels tedious to click back and forth for the same thing multiple times. Not that this is a big inconvenience or anything, just a suggestion that I think would improve things.
Overall, the game looks very nice and I enjoyed playing it. Great job!