As others have said, I think the flying is simple and satisfying.
However, the aspect I think is the most interesting, other than the terrain generation, is the AI. It's simple, yet effective. It makes the world feel alive. They're quite competitive when it comes to food, though.
I also like the sound work, graphics and animations in this game.
The only thing I don't like about the game is how fast the player dies of starvation - I think it's a tad too fast.
Otherwise, I don't think there's anything to complain about.