Think about ways you can incorporate all this over to your own ads. But don't think just onedimensionally. Think too about ways you can laterally apply various techniques, styles, approaches,and rough concepts over to all kinds of different marketing applications you currently engage in."
'a rough diamond' is one which hasn't been cut and polished...and in that condition, is far from a thing of beauty.
Similarly, 'a rough concept' is as susiedqq said, the start of a good idea that needs some work on it. It's like Niki starting out with the idea. the rough advertising concept, that their trainers were 'excellent', top class in quality, first in the field in design and fashion...and these rough ideas, this rough concept of 'they're the best' was refined down to that simple tick mark they use as a logo!