Mechanically, this is fascinating. Functionally, it's off-balance. I think the primary hitch is that the "lift" (flapping) is a Fixed amount.
There's no small or large flap, nor a sliding scale, which puts me in mind of 2D platformers that don't allow you to control the height of your jump, you just always max-height jump, and the jank feeling of that is about the same here.
Similarly, about the only way I found to "drop" in height was to turn sideways until Vertical, and that would help speed descending, but it's effectively just a controlled crash towards the ground at that point. There's no "dive" to have a controlled faster descent.
Combined, it means that any movement beyond small adjustments can quickly and easily spiral out of control, and put you on the ground upside down, or desperately spamming the flap to try and gain altitude even if you corrected the alignment.
In terms of the fighting, I'm glad the ring collection and it never overlapped, that would have been a true nightmare. It felt MUCH more approachable with the decreased HP, but I kind of would have liked an option to keep the 3D aiming, just with the reduced HP, especially for the following fights that have MANY more enemies at once.
All said and done, I think this would have gone perfectly if there was a bit more precision control available in Verticality. It's very fun to play with as is, but as soon as maneuvering to get into rings and fighting hits the table, the lack of a practice mode and need to reset and re-watch the tutorial over and over is definitely not helping with people getting annoyed. I've got rather a lot more tolerance for jank from playing lots of unfinished games, and a fairly wide variety to boot. This is a very nice pilot concept for a flight simulator system for piloting a dragon with wings, just needs more capacity to make small adjustments, and maybe a one-tap button to make them level out? Can't say I've played any flight sims, so my opinion is based on stuff like flying helicopters and jets in combat games.