You should try to answer your own question by asking the question: which theory leaves more unexplained?
Every theory has something left unexplained, since one can always ask a further why. The question is: at which level do you consider a further why to not be appropriate? When someone creates a “mystical theory of reality” it’s usually without any details fleshed out. Hence, the way it actually works is a mere postulation and doesn’t tell you anything more than what we already know about the physical nature of these mystical experiences.
If a “theory” doesn’t tell us anything about how it does things nor does it predict any new things consistently, it is a sign that there is no reason to believe it. A theory is only “necessary” to explain something when it is obvious, in front of your sight, has compelling evidence for it usually through predictive power and other things, and simplifies the data in a neat way (which is why mathematical laws are so useful).
An explanation in a theory that is hard to vary in its details is also a sign of a good theory. For example, “goblins did it” can be used to explain anything. It fits all the data. A law such as Newton’s second law can only fit a certain set of observations. If suddenly observations broke that mathematical pattern, the law would be falsified.
The analogy with computer programs is very useful. Simply ask yourself this question: if all observations could be represented as a simulation from a computer program, would the currently proposed theory reduce the lines of code needed to generate the number of observations? If the answer is yes, then combined with additional evidence, it’s probably necessary. If not, you can probably throw it out or atleast not worry about it.