Thanks for taking the time to record, it was really fun to watch and hear your thoughts, although it did make me feel a bit bad about a couple of design decisions :| The maps and pickaxes are indeed capped for a maximum of 6 hits/spins, the thinking was that I didn't want runs to drag on too to the point where it stops being fun but that may have been a mistake. The scaling is essentially Fibonacci so it would likely outrun you quickly enough regardless. Round 18 is the best I've managed too, could've balanced things a bit better with more play testing but that's the nature of jams.
I considered adding a reroll to the shop, probably should have but I thought it might make thing too easy and repetitive between runs.
The soft lock is one that occurred to me on one of my early play tests but then something else needed fixed and it was completely forgotten!
If you've any inclination to go back for another run my only suggestion would be to be a bit more trigger happy on buying gems, once you get past 25 items in your inventory each spin will pull a random mix so you can potentially start to crowd out the bad early game stuff!