I'd have to go with Marc for racing and Neil for freestyle. Not trying to be on the bandwagon, but I think that those two are some of the most eligible in their categories.
I remember back when Marc first started driving in Atlanta 2006, where he was the 2nd fastest qualifier and made it to the finals against Meents. Since then he's had a few semi-final appearences in Vegas, won racing in a few places, and even managed to get runner up in this year's World Finals. He's come this far; he's only a few short steps from being the champ.
As for Neil, what else needs to be said? Over the last year or two he's become one helluva freestyler, and a pretty good racer too. In Orlando 2012, where he took his first Double Down, he was fast in racing and had that amazing save in freestyle. Honestly, I'd say he's a contender for both titles.