A fair mix, though I'd say it errs on the side of high fantasy because, well, it's more or less a D&D game.
I'd say my setting's basically a mix of Medieval & Renaissance eras (well, with the mix & match of weaponry from various eras & all that). No gunpowder (at all--don't care for that in D&D), though some "advanced" tech like the printing press, large walled cities (with sewage systems) and large trans-oceanic ships (and not just world travel ala coast-hopping) are available.
It's high fantasy (well, as high fantasy/magic-prolific as D&D is in comparison to Conan, Lankhmar, LOTR, etc.), but it's nowhere near the level of a magic-rich environment as Forgotten Realms or Eberron.
Allow all of the core PHB races & classes (don't allow subraces ala drow & duergar, etc.--they're just standard elves & dwarves [etc.] w/ different complexions), plus psionic core classes, the CG/LE/CE paladin variants from Unearthed Arcana, and a few core classes from Complete Warrior/Divine/Arcane/Adventurer. Considering allowing changelings from Eberron as well, as well as orcs & xvarts (goblinoids are off-limits due to plot elements/reasons). May allow 1 PC to be "reincarnated" as a warforged if they die in game (the idea sorta remains me of the sentient iron golem in the Forgotten Realms comic, which I thought was cool for a unique character).
The main adventuring area is more-or-less pseudo-European, though there are other pseudo-Earth cultures present (though I don't have subraces, I do have different regional "flavors" for various groups--the northern dwarves thend to be chaotic, pale-complexioned, barbarian-pseudo-Norse types (the notable NPCs are reminiscent of the surviving Norse gods of Ragnarok & their kin), while the southern dwarves in the desert montains are more lawful, dusky-complexioned, tending towards monks & samurai (sorta a weird sort of Arabic/Persian/Japanese/Chinese mix--the first 2 due to environment, the second 2 due to culture/order/structure).
Elves & orcs are low in number & tend towards isolationism (they nearly wiped themselves out in a war about 5 centuries ago). Gnomes are actually a half-halfing, half-dwarf mix that bred into a race of their own. Halflings are an integrated part of the dominant human cultures.
It's got it's own sort of spin to things, but it's generic enough to fit into a D&D mold & meet most player expectations of D&D (unlike my past homebrews).