Let me clarify just a bit for your Michiganders: My opposition to Dearborn is not related to the weather in Dearborn itself in April, but rather to the weather between the West Coast and Dearborn in April. Would you want to cross Montana, the Rockies and the Dakotas in early spring in a Saleen with summer tires on it? Again, I would much rather attend such a gala event in a warm weather state.
It took us about 5 hours to get through the DC area traffic. Ended up going another route home. Was thinking about going to the grand national next year but if I have to use the beltway again, it's not gonna happen.
As I think the 50th should come home to Dearborn, the Indianapolis Motor Speedway would be a viable alternative. It's centrally located. The racers could use the F1 course, there's enough infield to handle all the car, and IRP is only a mile or two down the road for the drag racers. Only possible issue is the Indy 500 being a month away.
I doubt that the 50th will be held in April since 4-17-2014 is Holy Thursday and that leads in to Easter week end.