The concept is intriguing and the execution thereof well done in terms of pacing and interaction. The platforming can get tense at times, which is good. The graphics and music fit well. The controls are tight and responsive overall, and while there is a delay between jumps (flaps?) that is something the player can get accustomed to and does not take away from the experience.
A few bugs here and there: I found I could not jump while pressed up against a wall, which can end in character death over bottomless pits. One can also jump and walk above the bird god and go past the wall, making the bird god spout all of his text immediately. Regardless of what ending you supposedly get, the game seems to crash. I am playing on a Mac, so maybe that's it, but annoying nonetheless.
The most questionable thing about the game in its entirety is the random lightning bolts when you choose to feed the chicks twice. They seem entirely luck-based and there is no indication, sight, sound or otherwise, where they will strike. In addition, if the bolts hit a platform and you happen to be on that platform, the bolt's kill box tracks your character rapidly. While not literally as fast as lightning, the character is slow enough that this makes the latter half of that path completely luck-dependent and makes for a poorer experience overall, especially when one chooses not to break the eggs and so checkpoints are few and far between (i.e. there is only one of them).
Overall enjoyable, but needs a few fixes that could truly benefit it. I enjoy the concept but my least favorite bit was the randomness of the lightning bolts. Maybe keep them in but give some kind of indication as to when they will strike, and make it so they can't hit the bird while in flight unless there's a visual cue.