2003 DTS Snow performance

I have a 2003 DTS that came from the factory with Michelin Energy Tires on it. With these tires the car is almost imobilized in the snow. I do not want to change to snow tires for winter driving. What I would like is a good all season tire that would get me through most of the winter we have here in Buffalo. I have looked all over and can only find tires that rate marginally in snow performance. This car is so bad in the snow that I am considering getting rid of it in favor or somthing better. I have been driving cars in buffalo for years and short of my old rear drive cars, this is by far the worst in the winter. Is there anyone with a Deville or DTS that has found a good all season tire that works in the snow?
-Matt