Great opening cutscene, I wish it was narrated :)
It seems that you heavily copy "A Story About My Uncle" both story (missing uncle/daughter), art (flying islands), and mechanics (grappling hook) wise, at least as I see :D
However, in "A Story About My Uncle" you have gameplay challenges because of the hook charges, and here you lost that by allowing the player to use the hook for an infinite amount in the air.
So the only challenge that you have is where to jump and how to finish the game :(
Nevertheless, the work that you have done in 1 week is extremely huge and definitely worth the respect!