Dang this is awesome! What a great concept for a game.
1. Not sure which crack you're talking about. The big one going across the geode? Or the little one I'm trying to hit in the little 'quick-time' event. If it's the big one then yeah the glowing effect is quite clear. But the little yellow cracks could be a little longer maybe.
2. Aiming for the cracks is super satisfying and a great mechanic, however It needs more tolerance acceptance for the clickable area. Sometimes it looked like I hit it perfectly and I miss - which makes it annoying haha. But the sounds work great with building a combo of clicks.
3. Yeah, pretty keen to keep progressing, mostly out of curiousity to see how the game gets more complex or how much depth there is to discover.
I'll also say I agree with wburd about the cursor. From using a computer I'm assuming the top left of the hammer is the clicking point. I wonder if it would read better if the animation rotated from the top left of the cursor art, so the pivot would top left or the cursor artwork (just an idea idk)
Just spent a solid 45 mins playing this (No idea how that could take 20-25 mins)I think it's great. A bit of feedback -
The mole hitting the geode is great but annoying how it moves the quick-time yellow crack since It keeps jumping away before I hit it. If he just chilled there hitting the geode and not affect me, it'd be great.
It felt like it took ages before I finally got ahead of the progression flow. I felt like for half the game I wasn't making enough progress fast enough. I felt like I was doing far too much clicking by myself before the mole appeared, and even then there's a lot of clicking (although, this might change a lot of the quick-time yellow crack was a bit easier to hit?)
Thanks for sharing your game! I had a great time! 
WOW, 45 minutes, respect to u man, thanks for the deep run!
Yeah, originally this took 10-15 but I started tweaking the incremental functions and things might have gone a bit out of hand, sorry for that I'll adjust it a bit and try to get closer to 20-25 mins, I was afraid the whole thing might have felt rushed but clearly it went the other way round xd
The mole knocking the crack away is new info, I hadn't noticed :/ fixing that rn. Also making the middle game a bit faster in terms of pacing, thats noted too :)
"Had a great time" makes me extremely happy, thank you!