UPDATE 2:
In the past couple of days I added a scene handler, menu, screenshake when you hit an obstacle, a couple sound effects and screenshake!
The menu caused a lot of problems because I wanted to be able access it from any scene. It alone probably caused 2-3 hours of debugging. In the end, my solution was store the previous scene in a variable, and to that when I exit the menu. My scene handler is a mess, but I got it to do the bare minimum after way too long working on it.
This guy [the restart screen] was also a pain, just because I kept getting distracted and forgetting what I needed to do.
I also rotated the gameplay surface to make it look like you're going down a mountain. Here's a scuffed gif of what everything looks like right now. The background is a lightly edited version of an image I found on unsplash, with a color overlay based on how close you are to the end of the round. My idea is that it shows different colors of light throughout the day, and each round is a day/night cycle (the more obvious representation of cycle is that the character will be on a bicycle).
As you can probably tell, I'm on summer break right now and don't have much to do, so if anyone has suggestions for features I'm all ears!