I do believe that value is in the eye of the buyer and that knowledge and understanding is always the best ticket.
Knowledge and understanding of people as well as technology. The listener is perhaps the most important component in any system for determining results. Most of the rest comes down to a few fundamental principles to follow to get good results and the rest is mostly personal opinion and preference, including how to best tweak and how much one spends or on what.
I consider overemphasizing the tweaks or fine tuning before addressing the fundamentals to be an exercise in futility to be avoided at all costs. i tend to disregard anything said about any tweak or fine tuning unless put into context relative to the primary factors that determine results prior. Put the horse before the cart as they say. Anything otherwise will be a never-ending blind chase that benefits the vendors only.