Lots of cool ideas here! Having to balance between controlling two characters can make for some really interesting challenges. I think one way to explore this idea more would be to have both characters in a combat encounter at the same time, but have the rooms be slightly different so you have to actually pay attention to both screens, although it's also possible that that would make it too difficulty to actually play. I liked the idea of having one character have to fight the boss while the other character balances when to pick up potions, but I ended up just paying attention to my boss fighting character and ignoring the potions.