I opened the game. Bam, just dropped straight into things. So I just started flying around and picking things up. The UI communicated the rest. The way new mechanics are introduced in this just works so seamlessly, having the purple items circled around the lanterns so you learn how to active them later is fantastic, and having more enemies spawn later in the game also made me accidentally learn how to defeat them. I never knew what I was meant to be doing from the start, so I just did the things that could be done, and by the end I had a goal set for myself and a sense of direction.
On the flying physics themselves, they didn't immediately click with me but this also isn't really a problem, it didn't take long to feel like I'd mastered them after a while of picking up purple triangles. Maybe only bad thing about them is that sometimes I found it difficult to avoid crashing into an enemy, even when I could see it coming.
Speaking of which, the one thing I didn't like was that you dropped all of your collected "stuff" when colliding with an enemy, although that didn't stop me completing the game. I would have liked being able to pick a portion of the dropped items back up in a sonic-esque manner.
Still, really fantastic game overall, I mean it! Very enjoyable!