If I'm going to mine all day, I'd kind of prefer to hold down LMB to mine instead of doing powershots all day, assuming that's any better than spamming. Speaking of powershot, if you release then hold down LMB too fast(ie during the swing animation) it won't register, so you then have to release and hold it again. Bad game feel, I expect it to start charging as soon as the animation finishes.
In the shop room with the green scarab, you can jump from the rafters to skip the elevator, though that's silly since the switch is right there.
I eventually got all the pickaxe upgrades and got the crown. I also saw the WIP area. I then decide to kill myself and it seems like there is no saves so that's too bad.
So fairly fun in a clear cutting sort of way, but not too much going on. On the flip side, due to that there was no difficulty in learning mechanics without a tutorial, like throwing things to flip switches, lighting dynamite on fires, merchants, etc. Biggest complaint so far is why it isn't fullscreen.