" No sane Catholic would ever suggest that Mary does any of the things you describe separate from the power and will of God."
Many of the statements I've read here and on other Catholic info sites leave me with the impression that Catholics view Mary as some sort of demigoddess.
I can't fix the impressions you're left with. I can tell you what the doctrine of the faith is (to the best of my flawed understanding), and apologize for the poor catechesis of some (many? most?) Catholics. But failure to teach the truth doesn't change what the truth is.
Having said all that, it was C.S. Lewis, I think, who said that everyone you meet will end up either as an everlasting horror and shame in hell, or as a being of such glory that you would be sorely tempted to worship him or her. The glorification of the saints of God by God is not a trifling matter.