Very good game! Nice pixelart!
The problem I had is, a lot of times I was jumping to any platform that I can't see. You must memorize the map or you probably fall to the ¿lava? ... Maybe a minimap could help ;)
It's true. Gameboy resolution is low and so difficult to include a minimap.
Another way could be, make another movement like crouch and displace camera to below. Because problem always is that you cannot see platforms down, but you can see it on the left, right or up.
If you continue the game I'll see it :)