To get this thread moving in a more productive direction.
One of the key features of the D&D zeitgeist is that everything is one. Every D&D game (except mine, BWA HA HA) has elves, dwarves and halflings. Every D&D game (again except mine, BWA HA HA) has drow, even though they were pretty specific to Greyhawk at first. Eberron has lately introduced the shifter and the warforged, but now they've shown up in the MM3, with text on how to fit/shoehorn them into the FR; I'd also say the chances are high that in the future, a putative 4E will give them a prominent place in all official settings. The classes, feats and spells in the PHB, and the monsters in the MM, are a powerful unifying force that encourages most D&D games to be fairly similar, at least in the broad aspects at a given level.
One of the key features of HERO, on the other hand, is that it's a toolkit. It's not assumed that you'll use every power in the book in a campaign. Instead, the assumption is that you'll select a particular genre, tone, and power level, and tailor the available options to suit that. A lot of space in the HERO books is devoted to how you might do this, what effects are suitable for what genres, etc. Even if you go to a particular genre, Fantasy HERO devotes tons of space to different sub-genres of fantasy, how to create a particular feel, and so on. There's nothing to say that one Fantasy HERO game will be anything like another Fantasy HERO game (unless you start using the prepackaged stuff, but that just comes back to the creeping D&Dization of HERO).
Perhaps D&D could use something like this. You could have a book (or a series of books) that discusses different sub-genres of fantasy, and what rules elements are suitable for each sub-genre. So if you wanted a l*w m*gic game, the book might talk about things like what l*w m*gic actually means (many things to many people), dropping some classes, making magic harder to use, what sorts of challenges are appropriate, etc. Ditto for a h*gh m*gic game, although there the focus might be on things like how to power up the "mundane" classes, the tradeoff between flashiness and verisimilitude, the different types of h*gh m*gic, or whatever. Sorta like OA, but with a broader scope.