In fact, I'm playing! Taking a page from Jeff Rients' book, here's my guy.
Haakon Moonarm, Scourge of the Old Ones
Haakon is a Bone Man from grim Carcosa. Apparently, he's got some weird birthmark that prompted his tribe to consider him the Chosen One, destined to strike down the Great Old Ones, but then he got banished for some reason. Rumors state that it has to do with his cybernetic left arm. Slow and plodding, but his speech has the measured quality of a scholar or warrior-poet.
As the picture suggests, Haakon bears a resemblance to Frazetta's Death Dealer, except he looks like a skeleton. He has occasionally been known to cover his skin with ash or paint so as to downplay his skeletal appearance, but it's doubtful he'll do that in the races.
Edward "Red Ed" Czarnecki
As best as anyone can tell, Eddie is a Polish immigrant, a factory worker in 1920s Chicago. An ardent Socialist who claims that he was "too extreme for the IWW," Eddie somehow fell into Carcosa and ran into Haakon. Recognizing the Great Old Ones as another oppressive hegemony, he threw his lot with Haakon and the two have been buddies ever since.
Oh yeah, one more word about the whole "Polish immigrant in 1920s Chicago" thing: most people think that, but Eddie makes reference to things that are in no Windy City anybody has ever heard about. Some of his lurid, retro-futurist descriptions suggest something more akin to Lang's Metropolis or whatever bleak future civilization will eventually give rise to Wells' Morlocks.
As the picture suggests, Eddie bears a resemblance to Charlie Chaplin in Modern Times. He deviates from the picture by being more disheveled and possibly on speed.
The Blessed Brian
The Blessed Brian is a bizarre vehicle, some sort of sleigh or chariot. The body is formed by what appears to be the inverted shell of a giant horseshoe crab. It is pulled by some large, mutant creature from the Carcosan wastes — something resembling a ten-legged camel with no head. The whole assemblage is shaded by a large, garishly colored brolly or North Korean traffic girl's umbrella; the brolly is an assortment of reds, oranges, and jales, like a radioactive Carcosan sunset. The pièce de résistance, however, is the figurehead mounted on the front of the sleigh. It appears to be the limbless torso of screen and stage actor Brian Blessed, set to gnashing its teeth, singing, and yelling at all who draw near.
Joan of Shark
Addendum: Robert Guy released the racing lineup, and you should look at it. The Ayatollah of Racin' Rollahs is probably my favorite, based upon his over-the-top personality and, ahem, "unique" look. Red Ed roundly claims that the Ayatollah has the look of someone who does not comprehend the emanations of the electromagnetic spectrum.