That's a very difficult question for me as I really like variety. But if I HAD to smoke only one blend, then it would probably something that offers more than just one dimension depending on the age.
For me, that would probably be PS Luxury Navy Flake. I wouldn't necessarily call it my favorite. Maybe not even in my top 5 blends of all time. But it probably changes the most of any other blend in my cellar with age.
When it's young, it is bright, sweet and almost aromatic in character. But as it ages it develops deeper more nuanced flavors more akin to a darker Va/Per blend.
So in essence, I could smoke the same blend, but depending on the age I would get very different flavor profiles so I can still enjoy the variety of flavors that I like.