I have just completed the first set of four levels, and I am in love. I was in love from the time I saw the banner icon in the bundle I bought as I was scrolling through, and I only regret that I didn't start playing right then and there. This game is beautiful and wonderful, and I love it. I haven't gotten very far into the story, but it's fascinating. The music is beautiful, and I love how it gets added to when you fly or slide. The art, though. The style is gorgeous, and it's what first interested me about the game.
The strong use of colors, the delicate but bold blocky shapes, and the way values etch out a landscape primarily in monotone- I love all of it, and the animation is smooth and beautiful.
I love the sense of movement in the game, and how momentum sends you swinging through obstacles. Even though it runs a little slow on my computer, as I am playing on a laptop not meant for gaming, it's still loads of fun to swing through the world. It's challenging, yet very enjoyable.
Overall, this is an incredible game, and if you have the soundtrack up anywhere (spotify, bandcamp, soundcloud, etc) I will definitely be listening, because everything about this game has wonderful vibes.