Quick point about the Holy Spirit:

Ever notice how the first Revelation (Old Testament) seemed to reveal God the Father to mankind, while dropping some major hints about His Son? Then the Son was revealed to mankind (boy was He ever) in the second Revelation, while dropping some major hints about the Holy Spirit.

The Third Person of the Trinity is so difficult to get a hold of at this point. At least the names "Father" and "Son" give some specific insights into the First Two Persons of the Trinity. "Holy Spirit," on the other hand, seems a purely economical name that doesn't really tell us all that much.

Perhaps the third and final Revelation (presumably the Day of Judgment) will also constitute revelation of the Holy Spirit.

I don't know. Interesting to think about, though.