There's a world of a difference between acknowledging Mary as a singularly graced women in the plan of God and calling her "mediatrix of all graces", "co-redemtrix", "mother of all mercies", and other ridiculous titles.
The blatant audacity of Papist sophistry to imply that the Logos can have His mind changed by the whims of a mere creature are at best blasphemous.
Not to mention the clearly unbiblical "privileges" involved with Marian devotions, such as the sabbatine privilege (having your soul rescued from Purgatory the next Saturday after your death if you wear the brown scapular), various promises if you regularly pray the rosary (such as avoiding misfortune, merit glory in heaven, obtain all you ask for, etc), promises if you pray certain novenas, etc.
If even the titles of Queen can be legitimately conferred by virtue of her giving birth to Jesus Christ, the overwhelming excess of Rome taints any use of the phrase and, like the Bronze Serpent, must be cast out.
And before I inevitably am accused of hating Mary, let me categorically say that I bear no ill will toward her.
She was and IS a saint, given a tremendous place in the plan of salvation by Almighty God and as a result is blessed.
However, this is not license to give her undue praise, veneration, and attribute nigh-divine things to her.
My disagreements with the Roman practices involving Mary does not mean I hate her, just as my disagreements with Papists does not mean I hate them.