Not very, wouldn't be "super" natural by definition if they were.
How successful have scientific explanations been in settling issues of value and worth and what our purpose should be as human beings?
2) How many scientific theories are dependent upon an unquantifiable and unknowable power that is impossible to observe or predict?
None, by definition. Science can only deal with that aspect of reality that can be detected by the senses (or their extensions) and has a quantity and location.
The rest of reality is invisible to pure science. I don't know anyone who would like to live in a reality limited by only that which science knows. Do you?