Given my fickle taste, this could be a self-defeating question, but I imagine part of the exercise is determining precisely what type of weed can stand being smoked for the long haul without boredom or frustration? In other words, a solid, reliable all-day blend?
I would normally say Squadron Leader, solid and consistenly pleasing. But this would only be possible in an alternate bizarro world where Sam Gawith is, you know, actually SOLD somewhere.
My Mixture 965 comes to mind as well, never dull and always has depth for me.
On the drugstore baccy side of things, I'd say Walnut.
If I had to choose only one Virginia-based blend, I would go with HH Mature Virginia as being most adaptable and pleasant over time.
Well, that was four, but it will do for now. . .