Fun simple little dungeon crawler. Not sure if you're still working on this or not. If so, I hope the feedback is helpful.
Coins in chest is cool, but you might consider adding an occasional drop to monster kills. Or something to incentivize the player fighting the monsters.
Running out of health isn't really a problem. I found myself letting my health get to 1 and then trying to run the dungeon on that 1 health. I didn't want to spend that money on food because I knew if I was killed I'd just go back to the beginning of the furthest level. If dying sent you back to the menu, I'd manage my health better. That would work well with monsters dropping money and/or food. Maybe coins just come from chests and there's a finite amount and monsters drop food occasionally?
The upgraded swords didn't seem to behave differently from each other. Maybe that was a planned feature and you haven't got there yet, but increased range or speed or damage or something would be cool.
Didn't try the wizard, so I'm not sure how that character differs, and I didn't try replaying a dungeon I had already beat. It would be cool to be able to reply and fight for more coins on an easier level to buy the health upgrade to make later levels harder if the player wants to. That would give the player a bit of a strategic choice to make.
Some feedback when taking/dealing damage would be good. I bit of knockback or a sound or something to help the player feel the attack a bit more would help the game feel a bit juicier.
Anyway, I really really like what you have here. I'd love to see a complete game. Someone else mentioned a physical version of this game, and I completely agree. Once you finish it, it could totally sell. Finish the 2 dungeons you've hinted at in the menu, maybe add another final dungeon even. It would be a lot of work, but I'm certain there'd be a market ready to purchase.