Chevy Volt
Major lack of dealerships. For example, Idaho has ONE Saturn dealership. I live in Idaho, and it's four hours away. Nearest Chevy dealer is four minutes away.
I agree it's wholly unrealistic, except maybe as a plan to kill of Saturn and greatly hurt the other brands as well. Well, Pontiac would love the Astra. Aura & Outlook = almost zero development dollar extra sales. (well, the Aura took some development dollars, but they were surely all made up for in development savings for the new Malibu.) The Outlook is to the Acadia as GMC is to Chevy - it costs so little for it to exist that it takes very few sales before the cost is justified.
The Volt should go to Chevy. I don't think arguing it going to another brand makes a lick of sense unless it's as an additional model. Even then, I think the Volt should stand on it's own as a Chevy for at least a year or two. Work out the bugs, build Chevy's image, let the "early adopters" grab 'em up. Then add on a model or two in the upscale range.
I agree that GM would be well served to keep Saturn's image generally "green", but that doesn't mean hybrid & fuel cell only. That can mean efficient smaller cars and diesels as well. The Corsa will help green image, even in a gasoline version. Diesel Corsa, Astra, Aura. Heck yeah.
Making the Vue hybrid-only is a great way to ditch a lot of sales. Saturn sells a lot of Vue's (especially considering the lack of dealerships) - to think that you'd keep or make up for even half of those sales going hybrid only is a huge gamble. Keep in mind, Saturn is getting the attention and support it is because of import buyers cross-shopping it much more than other brands. Greatly narrowing the scope of the brand isn't a good idea at all, IMO.
FOG, does a plug-in full size SUV even make sense? How many batteries would a Suburban or Tahoe have to have to have an all-electric range of even 20 miles? I know common sense doesn't always line up with market trends and demands, but it just seems silly...
I can see a situation like Oldsmoboi is saying, with a hybrid version of each model (except I'm not so sure about models like the Sky). To make an entire brand hybrid-only may be brand suicide. Oh, and +1 on Electra name if Buick gets a Volt variant.