Final Lap Wii (RRPG) -- Racing RPG. A solid, arcade racing game + RPG hybrid. Offering more than simple parts management, I envision a career mode that involves massive exploration, floating mystical racetracks, puzzles, side quests, plot twists, etc. Your character ages (limited career) and can DIE in a fiery roadside accident! No save points, just an obituary in the Wii Journal. However, to avoid frustration, the spirit / ghost / soul of your character can be resurrected and find a new host. Of course, the process of finding a new host is not clearly spelled out in the manual and you must delve into the netherworld of magic to, hopefully, find your passage to blood and flesh.
The Wiimote would be perfect for performing witchcraft rituals.
For the folks who would be more interested in the RPG elements, there would be an "I suck at arcade racing games" mode... but this mode has to be unlocked by performing some ridiculous RPG-heavy tasks. As I envision it, RPG'ers would unlock this special mode at the same point that the arcade racing segments would get significantly more challenging.
Of course, folks could always opt for the more challenging racing.