Steve,
This really is a nice little mood piece and its mixed pretty well, too. (just out of curiosity, what program(s) do you use?)
The only 'critique' I have (and this has nothing to do with the quality of the music itself) is how well the music might adapt to a particular setting. The beginning of this piece is exactly right -- mood wise, musically and everything else -- to serve as background for the right sort of age setting. The latter part, where it builds up, while musically quite nice, changes the mood somewhat and if used in an actual setting, would tend to draw attention to itself. ONe of the hardest things, I think, in scoring for video or film is to create music that enhances the mood in a way that, well, nobody notices. An analogy would be the way a set designer creates the set design for a play: she wants to design a space in which all of the emotions, characters and story can be played out, but in a way that doesn't distract from the play itself.
The exception, of course, is when the music is intended to be the focal point, such as in a movie where you hear the hit song while you see the lead go through some montage of actions, or the big kiss or something or that wonderful end piece at the end of the first Star Wars movie when Han and Luke we're being rewarded for their bravery. But for 95% of the film, most people barely noticed the music, even though they heard it. But
everyone experienced the mood the music intended to create.
I guess what I'm trying to say is that in scoring music to accompany an age, we want the explorer to feel the mood, have an emotional response to the surrounding, but not actually notice, at least not in a direct way, the music. Does that make sense? I'd be interested in others thoughts on this.