Like I mentioned, I dont dislike Halo at all, but some things you said struck a bit on me, especially because you are talking about my area of trade:
Halo, as a game, is highly elegant. The designers integrated three aspects of combat - melee, grenades, and gunfire -- in a way that no prior game had accomplished quite as well. As a result, every single encounter in Halo is a fluid, holistic dance. The shield bar serves as a kind of timer, keeping the beat -- once it's depleted, you need to take a brief rest and then launch into another stanza.
Do you see what I'm saying? The combat is continuous rather than discrete, as opposed to a title like, say, Gears of War, which consists of punctuated bursts of violence while moving between cover, or System Shock, which is more atmospheric than balletic. In Halo, when your gun runs dry, you throw grenades, or you melee, or you go for cover, or you move to allow a friend to cover you. As a player, you move through a continuous network of actions -- a kind of enormous flowchart.
About the flow thing, no problem there, its subjective. You get flow playing Halo, yet Fallout fans find that flow in their TB combat.
Elegant in design? Simplistic you mean, not that it is a bad thing. Chess is simple in design, yet it is a good game. Then a again, chess is not a video game, and video games have much more potential.
Still simplistic is actually a good thing for the mass market, it is not a good thing for the advance in gaming industry.
But Halo is not elegant in the slightest, and the main reason for that will be explained when I cover the storyline.
The first is design. Particularly in Halo 1 and 3, the art style is gorgeous and elegant, and each enemy comes with a distinct set of behaviors that gives them a real personality. The AI is superlative -- the Elites in Halo 1 are, along with the Replica soldiers from FEAR, the game enemies that I most respect as opponents. The game physics do exactly as much as they need to in order to enhance the combat, and nothing more; they don't distract or overpower it. Halo 1's physics engine was particularly notable for its phenomenal handling of vehicles and collisions.
I dont think the design is anything to shout about to be honest. On the contrary. Look at the covenant. They are supposed to be a coalition of aliens, yet due to the design of their different species, they give me no reason to believe that they belong toghether, there's absolutely nothing that bonds them visually (except the weapons for obvious reasons). And that's bad design, not in my opinion, but in every designer's in the world.
The physics engine? you ever crashed with a warthog at full speed? Or when you fall from a cliff with the same vehicle, the way it behaves? Not to talk about the way everyone flies around each time a grenade detonates. I find Halo's physics extremely... unphysical
The second is atmosphere. The Halo story is beautiful in its minimalism. On the surface it appears to appeal only to testosterone-infused prepubescent males, but it goes deeeep. There are layers and layers of clues that are intentionally aimed (by Bungie) at a more mature audience, namely the older fans they grabbed with Marathon and who have remained interested for more than a decade. The story's enhanced by a masterful soundtrack (slightly overblown towards the Halo 3 end, I think).
So the story goes deep because of what exactly? Of the forerunner logs? Thats not story, thats flavour to enhance the universe. Universe which isnt that great actually. Ill try to break down the elements as best as I can:
The actual story (that is, the game plot) atleast in the first two games is poor atleast: no faction shows real conviction for their beliefs, the way most of the story is presented to you is done in the most old fashion and worst manner possible for a game: cutscenes. Every now and then, when you are enjoying your "flow", it all breaks to another ridiculous cutscene.
Remember when I said the design was not elegant, that was it.
Refer to Bioshock for an instance of a good way of presenting story and universe in games: You see what happens trough the "ghosts", audio logs, the few characters that talk to you, also clues in the environment (Who is Atlas?). Also you almost dont have non interactive sequences in there. And even one those was well executed (the "would you kindly" thing when you kill Andrew Ryan). So except for those 2 or 3 non interactive cutscenes, the rest of the story is presented to you in an interactive way, the result being that your play flow actually doesnt get broken. THAT is elegant design. Cutscenes every level to show you the story is not.
That also happens in Deus Ex, in System Shock, and others that I cant recall.
The same happens, to an extenct, in Freespace, because most of the story and plot developments are presented to you in mission, while you are playing.
Non cutscene storytelling is a big deal in games, because YOU are there living the story, you are not just an assed expectator.
The story itself is rather poor and mainstreamed as well... refer to Schismatrix (a book) for example, to get a taste of a well written story.
If the story is good or not is a matter of preference, however. As far as im concerned it was all good on the first one (although, again poorly presented), but after that it was rather meh.
But if there is some deep story here, I'm not sure I agree that it excuses the trash on the surface. Unless I'm very mistaken there's no good reason to bury something clever under one-dimensional characters, flimsy dialogue and deus ex machinas. Oh, but are we talking about the first Halo here? Because it must be said I actually enjoyed Halo 2's story and I haven't played Halo 3 at all. So my criticisms of Halo's story are mostly limited to the first game.
What he said
What Halo does, and the reason it's a masterpiece, is build a better flowchart than other games, even superlative games like Far Cry, Call of Duty 4, or Battlefield. It's more seamless. It sucks you into the flow state more successfully, and it has fewer flaws that might knock you free of it.
So lets get this straight, as objectively as possible:
Graphics and eyecandy asside (those dont make a game). The story and the way it is presented are poor and simple, the design elements are lacking in choesiveness (cool looking or not, again that's subjective) against a well executed combat gameplay (it is)... thats a masterpiece??
And on a side note its not difficult to be better than all those games you mentioned... they suffer from the same mainstream syndrome as Halo.