Very nice game!
On one hand: * The UI is relatively intuitive, and it is clear you spent a lot of time picking out little details, such as [clicking the Hammer button a second time cancels the destroy operation]. For every piece of text on the screen, it was easy to understand why it was there and what it meant. * The graphics - wow! Very clean. I very much liked the touch in the ending animation where the rocket flew up, and you could see the top UI as you passed through it. That was a fun graphical twist. * Great use of the theme! I don't think I've seen any game like this in the LD. Very innovative to use a Rubik's cube like that!
On the other: * The transition between screens (the one where all the cubes scroll onto the screen) is graphically pretty, but made me feel a bit of nausea. There was a LOT of movement going on, and when movements like these don't at least have, say, a bit of motion blur, it really throws me off. Of course, motion blur can be a bit much to implement in the time one has for a game jam, but there are a bunch of other options that (I believe) might help combat this (at least, it helps me):
[1] Slower transitions can ease on motion sickness.
[2] If you could make it so that the transition doesn't cover the entire screen, that would be helpful
[3] Taking time between the inbound and outgoing transitions. (Say, the blocks fly in, and instead of immediately flying out, you wait a second or two with the blocks all staying in place)
* The rubik's cube mechanics sounded fun in theory, but I ended up not really using them at all. Buildings that left the playing field had a low chance of coming back anytime soon, and so it wasn't interesting to pay any attention to them. The game then effectively became the same as it would if whenever a Rubik's cube move happened, three completely random towers appeared in place of the three that left. I'm not very sure about what could be done in place of this. I saw that in one of your replies above, you mentioned that giving the player control over which faces would turn could be a little overpowered. I agree. Although, maybe giving the user partial control would be helpful? For instance, if you decided the next face turn had to be from right to left, but the player gets to decide which of the three layers of the cube do the turn? Maybe that could be fun. * I did have a couple issues with UI, where sometimes a building would appear, and it took more time than it should for me to understand what sort of building it is. In fact, I sometimes found myself having a lot less information than I would have liked. The UI on the top of the screen was useful, telling me how many of each material I'm creating per second. And the UI on the right was useful, because I could hover over a building and know what each one creates. But I very much would have liked to see that on-hover info on each of the buildings on the playing field. And you know what? If there was room for it, I would have liked to see all of that info at the same time. Like, I'd want to look at the playing field, and immediately know not only how many gold pieces I'm creating, but which buildings are making more, which could be making more but are dormant, and which are using gold pieces (and how many). I found myself wanting this information multiple times throughout the game, and had to resort to hovering over the UI on the right and memorizing many numbers in my head, which was not so fun.
Altogether, (even though I talked for days on end on the parts of the game I feel could have been improved upon) I very much enjoyed playing your game, and I'd most definitely come back if you ever upload a post-jam version!