It wasn't that bad, but it just didn't have anything that noteworthy. I admit that the idea of dying by hitting birds is kind of lame. It's mostly because you don't even get to fight other planes. That seems like something that a hangglider would have to deal with. Yeah, it's weird that I want realism in a game. It just doesn't come off as that appealing.
Of course, you wouldn't fly around in areas with birds that much. You did have some decent designs for the birds. The game itself is just too dull. You could probably add in some good music too. Any premise can be done well.