Very polished. As Jupiter mentioned, there's no apparent goal, but I actually see that as a positive element of what you've made. It's aimless, peaceful, and relaxing. I liked picking up the birds, enjoyed gliding through the clouds, was sad when my birds left me, then calmly accepted death as the plane caught fire. (Hope there wasn't more to it that I missed :P)
Incidentally I made an Icarus-themed game for the Flappy Jam a couple months ago. It's also called Icarus but we definitely took it in opposite directions.
I'm adding your game to my collection of favorites from the jam. Good job.