I can't even get past the start point. The controls don't feel right. Holding to gain momentum would have been better than tapping the buttons. And also you should set your HUD canvas to scale with screen size. I started the game in low resolution and the HUD took up one-fourth of the screen. And the score text and the three monkey lives left sprites overlapped.
I can see what you mean from feeling like holding would be better to build up speed. In my mind I thought of kicking to get up higher in a swing with the impulse sort of pushes. But it's been very interesting to see that it wasn't intuitive to everyone and I've been trying to wrack my brain to think of ways to explain that through gameplay.
Sorry about the scaling of the external player! I mostly tested in windowed mode or on the webplayer and added external as a second thought. But thank you for the feedback! I'll take more care in future projects