I got to 6th wave max.
Left/right mouse controls feel fine but could be more sensitive. Up/down is probably just right.
Diagonal controls are weird. When I go up and sideways it seems that I can do way tighter turns that normally. For separate axes it controls smoothly, but combined it doesn't seem to control the bat with the same smooth characteristic. I quickly adjusted to the inverse Y axis, but it might be a part of what makes diagonal controls confusing for me.
Except for those problems, this game controls quite well. It really holds well while flying upside down and doing other stupid shit. That's impressive even if it doesn't have proper gliding.
Camera is too close, you could probably lower fov just a bit in exchange for shifting it back. It would be nice to be able to look around without affecting flight too much (alt use for echolocation?).
This game would be an absolute blast to play if it had a bit more inertia to smooth out the flight, and if possible actual gliding physics to trade altitude for momentum.
I would like to see more, if possible with another gameplay format for flight acrobatics challenges.