Holistic criteria are generally better than focusing on one element. Obviously, a deficit in one characteristic may be offset by a strength elsewhere. A weaker arm can be made up for with superior accuracy, for instance. DIfferent combinations can result in success or failure. Fit between qb and system is a significant factor, but in terms of individual strengths, I would favor the ability to read the defense and make a quick decision. OTOH, I often use the criteria of picking the name that would best fit the hero of a Western