When you say Rubens is more skilled, do you mean he is just more complex? When one programmer solves the problem in 100 lines and another in 1000, we usually consider superior the former.
I see what you are saying about the merit of distillation. However, Of Rubens, I would say that he has an increadable economy to his brushwork. He suggests with a few marks, what other painters would painfully describe in longhand.