Story - To be frank it wasn't much of one. Nevertheless the idea of text messages taking eight years to travel between recipients is an excellent plot concept and deserves a lot of credit for it. I can't really say much about the story, so much of it isn't in words that the only way is probably to watch the thing yourself.
This is one of those productions that gets its viewers simply out of reputation. And if any anime ever deserved such a way to maintain a respectable fanbase, Voices of a Distant Star would be it. This is science fiction, but this isn't some galactic epic or space opera. This is at heart a romance story dressed in the frills of science fiction, and remarkably succeeds in 25minutes to do what many series struggle to accomplish in 25 episodes: make its audience care about its characters and its plot. Possibly has something to do with the masterful juxtaposition of simple daily life on Earth against space travel and homesickness.
Animation - This is a difficult one. The artist used minimal strokes to come up with the characters' looks, and clearly didn't put too much effort into animating them. In fact, the faces actually look downright ugly in some shots taken from less flattering angles.
The designs for the both the characters and the mechs also seem quite uninspired. Perhaps it was deliberately left plain, but either way, visually not very satisfying although the mechs are well-detailed and structured.
The exact opposite occurs with the background scenes. Absolutely breathtaking. It's like the artist took a trip out to Mars and sat, facing the viewscreen, to sketch the scene as a replica. Absolutely beautiful. The colours are at once subdued, to match the general mood of the anime, and yet vibrant, wrapping the scenes in the sense of discovery and new experience so essential to science fiction. If you've seen Bartender, you'll know how the back bar with its bottles and glasses and all just looks like it's there. And with less CG to boot. Or maybe you've noticed how the classrooms in The Melancholy of Haruhi Suzumiya look so damn solidly real. Well this is something like that, only done half a decade earlier.
It's been almost ten years since Voices' first release, but I dare say even if it were only to be released tomorrow it would still be considered a top-notch animation.
Sound - The voice acting is good, but nothing to shout about. One gets the feeling that it wasn't that hard for most seiyus to accomplish anyway. The sound effects feel a bit hollow, with neither the epicity of most space battles nor the melancholy of an opera, but otherwise satisfactory and more than adequate.
The music is splendid. The piano piece is splendid. So splendid I don't even care that all the tracks are basically rearangements of the same piano piece. It's fantastic. At once disheartened yet hopeful, hesitant yet determined. It was like a pianist so depressed he doesn't feel the strength in his fingers to play, but tries to play in hope of finding that strength; that the pianist isn't sure what note he's supposed to hit next, but vows to press on and finish it anyway. Beautiful.
Characters - At first glance they seem quite bland, and even upon reflection the viewer will find he knows very little about them beyond their names. Yet so much emphatic response was generated, possibly by cutting straight to the core of human experience, showing us only the scenes and dialogue that tug at heartstrings without bothering with background etc.
I know of only one way to describe the behaviour of the characters: honest. Possibly it is because they are relating themselves to their closest friend, perhaps it is because they are always monologuing in solitude. But you know that what you are seeing and hearing is what you get, which makes the blandness and starkness (a death knell in most productions) seem all the more compelling here. Nevertheless, their lack of depth (although well-employed) is still a penalty in my book.