Winter/Summer/Autumn/Spring you know what I mean...
You could do your country a favour by running Rover, but whether or not they'd want to do that is questionable. Otherwise, why not bring back Volvo? That's if you don't want to stick with Renault.
BMW or Audi would also be welcome returnees, but then there's the eligability problems with how they drive. What about giving a newbie a go? You could try your luck with something from the VW group or even another Japanese marque. Mitsubishi ain't doing much else at the moment...