Thanks for playing and for the feedback! And don't worry, you're not bashing the game haha, I completely understand your points and there are currently some balancing issues with the game. Some features didn't make the cut and I tried making as many abilities as I could but I was quickly running out of time. So the drill ended up being overpowered, despite having a higher cost for etherdrill.
There are other ways to play, but they're not nearly as effective as just drilling dirt away. Struggle scales with Max HP, and Frost Fuel scales with Jets Fuel. Sparkles scales with everything, so it's the best move for a "balanced" playstyle. But currently there are no incentives to gather more jet fuel. The idea of having empty spaces has to do with this. I wanted to make the cave itself look like a dungeon, not just a "gathering bonanza". When I say I cut some things, I actually mean a LOT of things. I wanted to make a "radar" kinda thing so you could scout for resources, I wanted to make them more relevant at higher levels, and I wanted to make badges to "modify" powers based on elements (more fire pwr, more bio pwr, and so on), and I wanted to make it so certain enemies took more damage from certain elements. But well, maybe I get to do that after the jam rating period!
Anyway, thanks again! The feedback means a lot.