Current trends in architectural design require high-performance, low-power, flexible architectures that can adapt quickly onto the ever shifting and evolving application landscape. Finding the best architecture matching these stringent constraints is further limited by a short time-to-market window, which severely limits design exploration options. This work tackles these problems by proposing a different view on architectural flexibility, which can be exploited to achieve high energy-efficiency and performance instead of being traded off, by exploiting the advantages of reconfigurable architectures. Starting from a theoretical view, a methodology is produced for exploration of two different approaches in achieving high energy efficiency with two different architectural concepts: an architecture perfectly tuned to the application; and a new reconfigurable layered architecture, which can adapt its structure to match the application.