Races: All standard and optional races are available, plus kobolds who have been uplifted by powerful ritual magic to a level of intelligence associated with PC races (they specialize in sorcery and traps, and they’re largely loyal to the Champion of the Dragon Emperor’s armies). There are some flavor tweaks, most notably that steelborn are humanoids who have systematically replaced body parts and functions rather than having been created as they are.
Classes: All, plus the playtest monk, plus any other playtest class that comes out between now and then; as long as you’re willing to redo it once the real book comes out. I know Erica’s expressed some interest in playing a druid, and if you’re interested in something that’s coming in the 13 True Ways Book (monk, commander, druid, occultist, necromancer, and chaos shaman), we can cobble something together out of an available class between now and when the preorder PDF comes out, which shouldn’t be more than a few months.
Icon Relationships: To ensure a party that can all function together, positive relationships with the villainous Icons (Lich Queen, Army of Io, Order Cult, Magician) are prohibited, barring a VERY good pitch. Ambiguous ones are just fine, as are negative relationships with positive Icons.
Gender: This is a world where both genders are both equal, even in the physical arts; even being an adventurer-level fighter is about the will to tap into inner power more than how many reps you do (also I think sexism is boring); there are races who don’t utilize one gender to its fullest (the drow and the orcs come to mind) but that’s looked on by most others as a real waste of potential, and you’ll find quite a few talented female orcs and male drow working outside their communities.
Ethnicity: (as far as, like, European-versus-African-versus-native) IS more important, but (a) no one race has a position of dominance over another here, and (b) everyone associates ‘ganging up on each other based on race’ with ‘continent explodes’ (the black folks are a bit more insular, but being enslaved will do that, and of course there are plenty of exceptions). Obviously people are more likely to be friendly with people they have more in common with, but the world overall isn’t any more racist than, say, Seattle is today (which is to say not much on a universal scale). Asian people! Do exist here, the Order Cult was founded by a very diverse group of Asian separatists pulling a sort of Jonestown deal on the west coast, and plenty of their children have escaped and are making their way in the rest of the continent (the Herald of Progress is one of them actually).
Pantheons: Divine players have a bunch of options. The Europeans worship the D&D 4E pantheon, minus Erathis (dead), Tiamat, and Bahamut (worshipped by the Dragon Empire), plus the Triune Goddess (the goddess of cities and cooperation, and Erathis’s replacement). The Triune Goddess consists of the Angel, who protects the innocent, the Devil, who punishes the guilty, and the Wolf, who returns the city to the wild at its end. Africans worship their former local gods, who they have syncretized into basically the same loas and orishas the real world has. The Dragon Empire (mostly dragonborn, some yuan-ti and kobolds, and of course, the dragons) worship Bahamut and Tiamat, but they’re robbed of their good and evil connotations. Bahamut is the god of creation and giving, Tiamat is the god of destruction and taking. Midwives, artists, bakers worship Bahamut. Morticians, soldiers, bankers worship Tiamat. Bahamut’s more popular, but there’s an understanding of the necessity of the cycle. Much less likely to be relevant: the empire that rules Asia is officially atheist, but people from Qin could possibly worship divine principles (the Order Cult is a perversion of one of those) and Bharati gods never syncretized, so every tree and village has one, but very few have more than twenty followers (One of these days I think it would be hilarious to have a cleric of a tiny god like that in a game, constantly bickering and negotiating with their deity.)
Custom mechanics: I have a couple in mind and we’ll see how they work out. Stealing liberally from the Fate system, I intend to give out chips that can be cashed in for rerolls for suboptimal roleplay (if you do something that’s in character and makes your lives harder, I intend to reward that). You can also get a chip by giving me one. Secondly, I’m bringing a poker deck with me to games, and at dramatically-appropriate moments, you can go double-or-nothing with me on a single hand of blackjack. Double your damage dealt or none? Double your damage received or none? Double your reward? I’m open to negotiation.