Thanks for playing! So the parallax will be toned down later today. The three part background was part of the one asset pack and I have a parallax script with a speed setting that I attach to each image with a different speed setting for each. The image, however, needs to be linked as a material because you adjust the offset to get the scrolling effect. The script isn't perfect because I still need to define a reference to the player object in the inspector, but I'll be looking to make that dependency smarter as I intend to be moving between scenes seemlessly eventually.
As for time spent on the engine, I completely identify with that. I have another project with so many systems designed and just no playable content. I've been taking drawing and modeling courses on the side so I can start creating original assets for it.