OK what an absolute banger! I am a gacha player myself, so I of course love some good ol' mystery boxes. I would love to be able to skip forward when I've spent all my money, cause I accidentally spent all my money on upgrades, so I had no money left over for the rest of the run. Maybe selling/refunding upgrades could be a feature in the future?
On my second run, I pulled a bunch of rares on my first shopping spree, and due to the fact that I couldn't sell my first time acquired collectables, I was out a lot of money, and it was hard getting the ball rolling. Other than that, I really enjoyed the game, and I think it's a fun and unique experience! :)