Thanks for the feedback. I think the roguelike sweet spot for me (Hades also does this) is a mix of random upgrades earned throughout a run and purchasable, persistent upgrades. The random upgrades keep runs varied and interesting, while the purchasable upgrades provide a sense of progress and further mix up gameplay. I think this game would definitely have been improved by adding a random upgrade element--will definitely keep that in mind the next time I have a chance to make a roguelike.
Thanks again.