Aside from key controls and some way to restart and/or respec (I started a new game because I couldn't get past level 11), a fast-forward hold key could help (like, hold it down, and the second you let up it snaps back to normal speed, since it's quite easy to get quickly overrun once the enemies REACH you). It's also slightly difficult to click specific tiles easily, but overall, it's a really well-made and interesting game.
Making your game slow and tedious doesn't count as adding "hours of gameplay".... also either room 5 is bugged or just terribly designed, it's a complete blank.
The concept is interesting and fun, but the interface is awful (especially with that tiny font), it's really difficult to figure out what I can even do or buy.
Some way to deselect attacks would be good, and maybe a little more visual clarity - make it easier to see how many of each unit you have left and how much health they have. Overall, a very fun, compelling game.
Annoying how the fuel can run out while you're in the air... what's the point of that?? And the EXP can only be gained on the ground. At least provide main unit upgrades as well as enemy frequency - longer fuel time, etc.
PLEASE provide some kind of autosell/sell-all for the clothing factory. It's a pain to remember to stop what I'm currently developing to dart back to sell stuff.
An infintesimal chance of getting diamonds from mining/whatever might be good, because once the tree is maxed out, it kind of creates a bottleneck? I mean, at that point clicking on the tree doesn't do anything noticeable.
Very cute, very fun game. I agree that it needs a way to (optionally, maybe) hide bought upgrades, maybe a tab system for upgrade types, and a way to move quickly through the rooms would be nice. But overall, very well done.