Up in Smoke
For how ambitious it tries to be, AER sure is simple.
It's got a fairly smooth and intuitive control system for flying, which is kinda remarkable in itself. But all you really use it for is hopping from one island to another. (One puzzle requires flying through three rings, but no other part of the game makes use of aerial maneuvers.)
Its story is couched in environmental metaphysics ... or maybe it's a post-apocalypse fantasy? For all the cryptic world-building it hints at, there's no narrative payoff.
It's got an open world to explore, but there's very little "stuff" in it. Most of the world is, literally, empty space; like Wind Waker, but with air instead of water.
The puzzles leading up to, and inside, its dungeons are mechanically fascinating but never a challenge. At worst, you might have to manipulate a device once to learn how it works, then a second time to finish the puzzle correctly.
Its visual style is clean and high-contrast. But it's so visually simple, that it fails to stand out from so many other Unity3D games.
I sound pretty harsh on AER, when in fact the time I spent with it was quite pleasant. Didn't blow me away, nor did it offend or wrong me.
But it's two hours long.
AER comes across as a well-polished prototype. I appreciate the polish, but it's impossible to ignore the lack of substance.
Better than: A Story About My Uncle
Not as good as: The Legend of Zelda: The Wind Waker
On balance, maybe slightly better than: Oceanhorn: Monster of Uncharted Seas
Progress: Finished the story.