Some spoilers ahead:
Well, if the story is inspired or based on the works of H.P. Lovecraft (and it is), then it's pretty safe to assume that the Archaic is based on some of the cults from Lovecraft's works and from Call of Cthulhu PnP RPG, at least it looks this way. So, in my humble opinion, the Archaic must have more shelters scattered through many remote places around the globe (or through the dark corners of earth, if you like it more this way
), and even if they say that they use the findings for the "good of mankind", I wouldn't trust them. They can't be up to no good, diggind for alien artifacts and knowledge.
It would be great if we can see more of it in some future games, the story of Philip may be over, but the Archaic it's not.
"Ah, but a man's reach should exceed his grasp. Or what's a heaven for?"
Robert Browning