That part of your statement is remarkably consistent with the doctrine of the Immaculate Conception. You may wish to rethink it, as I know you have no desire to agree with Catholics on anything.
she was a vessel just like all others...
Funny how God would simply choose some random person, full of sin (in your opinion), as the vessel to hold His Incarnate Self when He took such care to define an especially precious vessel in the Old Testament (the Ark of the Covenant) (Ex 25), a mere shadow of what was to be (Heb 8:5).