Since the emergence of the German philosopher Immanuel Kant, the emphasis of metaphysical study has been switched from a systematic study of reality to a study of the structure of thinking about reality. Kant tried to show us that the structure of the mind will, in some way, organize the sensory information that the mind receives, thus proving that the way we receive experience is somehow tailored by the structure of our rational minds.
The biggest criticism of all against metaphysics is that any assessment thereof can only be formed within the particular metaphysical construct that is under analysis. Any description of the universe would have to offer an account of the observers within that universe and, consequently, an account of how the observer relates to the universe. The account of the universe, then, would depend on the way the observer views the universe. But the way the universe is would have some relevance to the account of how the observer views it. This leaves every metaphysical system wide open to accusations of circularity. An argument like that cannot be defeated.
However, if we perceive the correct metaphysical system, then the perspective from within that system is the correct one, and the argument of circularity becomes irrelevant.
With all this in mind, we are wise to only suggest ways of thinking rather than offer any degree of certainty that one way of thinking is the correct one. If a metaphysical system is incoherent or inconsistent, then we have a duty to abandon it, but if it is not falsifiable via some empirical method, then it at least stands a chance of being correct. Also, if it manages to offer a wide range of explanation, then it again has a chance of being correct. Furthermore, if it manages to offer a wide range of explanation without being so intrinsically broad that its explanations are vacuous, then all the better for that system. Even if we did ever manage to describe the absolute, fundamental principles at the foundation of the universe, we could probably never be sure that we were describing or establishing the right principles. However, we can explore different metaphysical systems to see if we can discover what it is we should seek in any metaphysical description.