Thank you so much for playing all the way and giving feedback. I made the first dungeon bigger to have more items put inside of it. It might be too big, but it's the second biggest dungeon floor in the game (The biggest can also be the final dungeon depending on what route you take). Most of the other dungeons have multiple layers or floors but the floors are smaller in size. But the demon selling only comes into play in the full/paid game where you can talk to wizard NPCs and pay them high amounts of money to get boss demons that you fought previously to become allies. So the final boss in the demo can be bought with gold in the next dungeon in the full game for example with all their skills and perks. I made the Oni harder to fight normally to force players to learn to easier escape or capture them, they have a multiplier to make them easier to escape from.
>Maybe selecting which demons to sell rather than selling them all would help.
It's mainly that way due to some RPGmaker's limitations with the base code and not allowing too many options on screen at once. Selling all demons at once was a way to make it easier. But I made it that boss demons that become allies through Wizards or demons got through special ways cannot be sold off in the main game, this made it so it's mostly demons you capture that can be sold and is mostly sold to get more powerful demons from NPCs. I should have had a way to showcase this in the demo, but that's why the mechanic is like that.
I'll take note of everything you stated and I'm glad you really enjoyed it.