That's actually so nice of you, thank you ! I'm really happy with how the music ended up, because it was the thing I was least looking forward to making. I hear what you're saying about the line-pushing trick. If I were to work on it more, I'd maybe introduce a cap on the amount of 'line' the player can draw, so it encourages them to be more strategic with it. Anyway, thank you for your feedback.
I've just did a replay in 2 minutes, the music really is spot-on, it has a real cool vibe to it :D! I want to start making my own sounds as well, it looks like it's as fun as game development.
Unrelated, I found a new cool trick while replaying, if you are stuck in a step-object, you can slowly drag a new line under the ball and slowly raise it vertically. But by no means is this bad design or something, I actually enjoy it more like this as it allows to be a little bit creative and less frustrated hehe