This is definitely a JAM game, took me about 30 minutes to 100%, but a mechanically very solid VVVVV-inspired game! My advice (for what it's worth) moving forward would be: don't be afraid to let players get a little lost to make the world feel bigger and more interesting. The original Metroid felt so big because not every path ended in a goodie; forward progress wasn't being made 100% of the time. If you want it to feel like an organic world instead of a Game Jam game, find that extra space, find ways to make it interesting, and start building a WORLD. This is a great start though - keep it up!