Not sure I quite agree - I think it's fine to have "persistent upgrades that smooth over repetitive parts of the game" within the proper roguelike genre, as lon

Not sure I quite agree - I think it's fine to have "persistent upgrades that smooth over repetitive parts of the game" within the proper roguelike genre, as long as they don't make the run easier. Gungeon is an example, with unlocks for skipping lower levels once you have demonstrated sufficient mastery that they're merely time-wasters rather than adding to the challenge.