Nice intro!
Guitars are nice.....atmosphere you've created is great. Production sounds fine to me....I'm no expert though!
Like the way it's building as we go along...nice and subtle and in keeping....oh it's over!
With the longish intro and the slow build AND the mood you've created I must admit I expected a longer song though mine seem to go on for ever so I applaud the brevity and apparently nobody has any attention span now, so perhaps you're right.
Enjoyed it anyway.