I have a hard time with a lot of Timelys because they all look the same. You'd have to give "classic" notation to about 2/3 of the Schomburg covers.
Classic should imply a run that stands out above the others. When someone mentions the title, that cover should pop into your head. When someone mentions the issue you should know it instantly. With a lot of Timelys, I still say, "which one is that?"
Not that they're not great covers, it's just saturation.
Same goes for moderns. There are a LOT of great images out there....every month. They can't all be classic.