The kindest thing you could say about 'Atlantis' from a commercial standpoint is that it didn't lose _much_ money - which is a shame, because it's a pretty good film.
A big break in direction for Disney in several ways, Atlantis does away with songs altogether, and pitches its Jules-Vernian era SF yarn at an older teenage audience than is usual for Disney features. Pretty clearly influenced by anime, 'Atlantis' comes across as Disney's first attempt to appeal to a different demographic. Unfortunately I don't think it's a demographic that Disney understood, and its second attempt at the same thing (Treasure Planet) would be a financial disaster.
There is a lot to like about 'Atlantis'. For most of the time it looks great (though not as great, I would argue, as the earlier 'Tarzan'), the story is appealing and so are the central characters. Milo is a chisel-jawed academic nerd who just happens to have a wild theory about the location of Atlantis. Financed by a mysterious patron and teamed up with a crew of odd characters who I'll discuss later, he sets off in an improbably advanced submarine (the film is set in 1914) to discover the sunken metropolis.
Milo is a likeable character, and so is the Atlantean Princess, but most of the crew of the ship are less endearing. Whereas it might be true that there is no standard comic sidekick in this film, I'd say that what you have is effectively a half dozen of them. I also completely agree with Inkwolf's complaint about tokenism in the choice of characters here. The black guy, if I recall, even has a native American parent, and he is a brilliant Yale graduate or something in 1914? Well it's not the only thing about the film which bends credibility I suppose.
If you can get over that tokenism, the characters themselves aren't too bad, though the only one I personally found straight out likeable was the droll French explosives expert. I don't know what they were thinking with the 'Mole' character, or what his obviously disgusting secret is ("Believe me, you don't want to know") but it worked kind of well.
Like I said, there is a lot to like about the film: a nifty action-adventure with an epic feel, no stupid songs, visually impressive, and at least a couple of solid central characters. So where does the film fall down?
Firstly I think that, beyond being influenced by anime in general, 'Atlantis' definately tries to take a leaf out of Miyazaki's book. There's nothing specific you can say which it borrowed from 'Laputa/Castle in the Sky', or 'Nausicaa', but it's obviously trying for the same FEEL. The backgrounds in the opening sequence in particular look very Ghibli-esque, and there's something about the Princess-warrior character who recalls to mind Nausicaa (though to be fair, it also recalls to mind various other things as obscure as 'Spartakus', the 80's French TV series).
There are two problems here. Firstly the makers of this movie simply don't have Miyazaki's sense of vision, inventiveness, spirituality or directorial genius, and in fact, as good as some of the backgrounds are, they pale beside Ghibli work from ten years earlier.
The second problem is that the super-imposition of Disney's formula onto a Ghibli-influenced story just doesn't sit very comfortably. If this were a Miyazaki movie, there would have been funny moments, but overall it would have conducted itself with a lot more dignity. Disney's approach, on the other hand, seemed to be that there had to be something funny happen every 20 seconds - literally, in some sequences. I just found the brigade of comic relief characters rather tiring after a while, and felt they detracted from what might have been a much more compeling story otherwise.
All the same, 'Atlantis' is certainly worth seeing, and if it can't mix it with Ghibli's best adventure epics, it's still a commendable stab in a new direction for Disney, which deserved to do a little better.