The art was impressive, both the assets and the shader, and the story certainly hooked me! The environment was beautiful, as was the subtle shift in camera angle as you travelled.
Unfortunately, I experienced quite a bit of lag and even when that seemed to clear up, the controls felt sluggish to respond. I wasted some time trying to get my cygnet to dive- not realizing it doesn't have an animation for it and technically enters a "diving state" while I'm diving. So I thought it just couldn't go past the log for a while.
It's also quite boring to just go on for long stretches of time with mostly silence. Apparently someone else heard background music, but I couldn't hear any? I heard birds chirping and such, but no music. The lack of a honking sound effect was also disappointing. Maybe it's a problem on my end though?
I think the game could have been more fun if it required more micro-managing of the cygnets as you acquired them. Maybe give them a chance to wander off or for certain obstacles to give them trouble unless you guide them around.
Regardless, great job finishing this game!