I will be very specific, to what exactly I noticed could be improved.
The animation of the box creation machine was shaking, but the inside icon wasn't. You either have the whole thing shaking (making an impression it's producing a crate) or nothing.
The mission picking was an amazing idea, but just wasn't followed through. I didn't see why I should pick either one of the options. It didn't tell me how many crates I need to make, or how much I get paid. I think this is the easiest thing to improve, since it's not too complicated, and it would add to the game greatly.
When in the spaceship mode, I got the asteroid encounter almost every time :( . I don't know the code, but I assume it's random, and I really didn't like that. Either have it always change, so no encounter can come twice in a row, or make it custom random, meaning after you already get asteroids, there's a much bigger chance to get shooting spaceships the next round.
But most importantly, the user interface. The first few times I got into the shop, I was extremely confused. And I read the tutorial first, so I more or less knew what each button does, but I really wasn't sure. I just think the whole things needs to be reworked. If you only want icons in the shop, make it so the player can mouse over the icons, and gets shown details about that upgrade. The text that made you buy an upgrade looked exactly the same as the text that was just there, and I had no idea if I click something what it's going to do. Also, there wasn't any way to reset after I make a mistake (which really isn't that important, but ^^reread my previous sentence and you see why I personally missed it).
I think these are the bigger things, that worsened my experience, but don't get me wrong! I very much liked the game, surprisingly spent a lot of time on it, and was grinding until I got all of the things on maximum. I really think if you rework it a little and polish it all the way to the end, it would have a lot of potential.
Anyways, thanks for reading. Hopefully, the feedback wasn't too long, too confusing, or made you angry, mad or sad. None of these are what I want, I would just love to see your game improved, since I really liked it and feel like it could get much better.
Keep it up!
Mravec