This was a fun little demo! Definitely a good start. :3 Most of any praise I could share has already been stated by others.
The main thing I'd like to mention is that the camera movement felt just a little too aggressive, throughout - worse in some areas than others. While the game's movement felt smooth for the most part, the camera movement was already giving me a headache/nausea/motion-sickness, just several minutes into it. TuT The demo was just short enough that I could complete it before it could really start to make me feel sick, but a longer session in the full game definitely would.
I wasn't playing it full screen - just windowed, about two-thirds of my screen. A smaller window or even more distance from the display (i.e. playing on a TV from a couch) might have helped even more. Regardless, while jumping around and moving left and right, sometimes the camera just flies all over the place, trying too hard to keep "ahead" and give a better view.
I am certainly one of those folks a little more susceptible to motion sickness from games, etc., if there's the possibility of it. But, even for folks less susceptible to that effect, the camera movement could still be described as a bit "janky" in the way that it can throw off player movement. There were several times that I went to make a jump and the camera started moving rapidly along with me, throwing off my judgement for the landing.
I saw that there were keybinds for zooming the camera, but it did not seem to want to zoom out any further, for me. One easy fix for the current style of camera movement would be to allow for zooming out just a bit further, so there's less need to rapidly/aggressively adjust when the player moves or changes direction (while still offering as much look-ahead). Or, there could be a slider in the options for camera-movement smoothness.
Hoping the best for the project, I wish y'all luck! :3