There's a good range of choices here which I like, and I think you've developed a good structure for the game to follow where you go someplace, fight a monster, and then move on. It would be cool to see this built upon with more story/text about the characters. It would also be cool if you added an inventory system and could get items from monsters. You could create a fun loop with that where you and the monsters both get stronger with each encounter, perhaps leading to a harder final encounter, it would be fun to see how far you could go.