This is a good framework for a fun game. The visuals and the sound effects are great and the little story at the beginning is fun. If you decide to take this project further, I encourage you to look at the combat design and the music. For combat, I noticed that none of the party members have any spells or abilities beyond attacking. Now, it may be that I didn't equip the right gear to unlock them, but a lesson I've learned is that most people will just run into combat without looking at any menu that you draw their attention to. You want guarantee that your core gameplay hook will be present when they get there, even if they don't look through the menus. Also, I would add background music, especially if you can get different tracks for the boss battles and the rest of the game.
That being said, I think you have a great start, here! Keep it up and you could have a fun, retro throwback!