Thank you for this succinct feedback!
We realize that the bug with the double jump can be very annoying, sadly we didn’t have enough time to fix it. The 15 second time is due to our knowledge of the game and its mechanics (we also played it for two weeks haha).
Glad to hear you enjoyed the speedrunning part and getting higher on the leaderboard. Also thanks for your ideas, some will 100% appear in the game!
Cheers!