Next gen impala..next gen G6 or G5..uhhmmmm...a small hatch for any of the brands is what ive been sketching up lately, its kind of fun. A light truck..like a colorado/canyon replacement. thats about all i can think of
Design something completely different where every surface of the car has a purpose or even a dual purpose. Sort of like a new Batmobile, but make it your own. Maybe it's a bread truck that converts to a bass boat... Maybe it's a combination Border Patrol vehicle/tornado tracking machine with a big telescope or a stun grenade launcher.. or maybe it's Dale Earnhardt Jr's prototype racecar that he uses to secretly abduct prostitutes with... maybe it's just a Malibu with side mirrors that can be used as a camping stove. Just go at it from a completely different angle.
Personally i would like to see a new design for Mercury, because today they seem to look empty, soulless. Other luxury brands, for example Lincoln has it's new design direction, beginning with the MKS (or even MKZ), Cadillac has it's unique front end and taillights and even Chrysler has it's unique front grill, so i think Mercury needs to have something too. Any ideas?