If you enjoy Buicks, please by all means do. Don't let the comments prevent you from enjoying.
Me, I personally don't like big boats that don't handle well, have automatics, that are ride focused, not handling focused. They exist for a reason and sell to a shrinking demographic. The Toyota Avalon is also the same demographic and guess what, it is NA only. My view is you should be driving a car, not be driven in it. Even a cheap car or truck can have sharp steering and tight handling, with moderate power and be fun. But that's me and just me.
I also don't like SUVs for the same reason, but like Buicks, have their niche and reason to exist.
Buicks in China are a brand, not a kind of car. Nothing more, nothing less. They are high end GM in China. There are Opels branded as Buicks, there are Chinese spec US Buicks,there are Holdens badged as Buicks, but they aren't the same as here.
Back to GM in the US. The only two brands that have an identity that is consistent with the product are Chevrolet and Cadillac. The rest are either images of marketing or simply too diverse a product line anymore to have a uniform message.
Keep going with improvements to Chevolets and add more manual transmissions and hybrids to boost fuel economy.
Keep going with Cadillac and keep improving the finesse and fit and finish.
Keep making Saturn - the US Opel or Opel like cars.
The rest - make them niche brands without their own product line or dealer network. Tack 'em on to the above franchises.
Do we need more than two Buicks? No. One big one that is really nice and one medium size and that's it. Sell them at Cadillac dealers. Keep Cadillacs as German competitors that are performance (Handling, not just power) and reliable (something German cars are not).
Ponitacs - what are these now? Sell the Solstice, and the G8. That's it. The rest are vanilla with "performance" branding.
Saab - align them with another import brand, not of GM. That's who buys them. Or sell them with Saturns.
The dealer network could be: Chevrolet-Saturn and Cadillac-GMC with sprinklings of Ponitac and Buick models that shine.
Make cars that don't rust (most others do), last easily 200k without issues (other do), with nice interiors, and are refined and you got a winner.
Toyota is making more and more appliance like cars, that's an opportunity to get a competitive advantage.
That's my business guess here. I have never had an emotional attachment to GM, save for driving a Corvette C6 or Z28 6-speed or the occasional Chevy pickup. The small block **is** a great engine in a lightweight, good handling car!!