Neither. But your mention of the Trinity is illustrative.
I would recommend following Martin Luther's admonition:
[S]he became the Mother of God, in which work so many and such great good things are bestowed on her as pass man's understanding. For on this there follows all honor, all blessedness, and her unique place in the whole of mankind, among which she has no equal, namely, that she had a child by the Father in heaven, and such a Child.... Hence men have crowded all her glory into a single word, calling her the Mother of God.... None can say of her nor announce to her greater things, even though he had as many tongues as the earth possesses flowers and blades of grass: the sky, stars; and the sea, grains of sand. It needs to be pondered in the heart what it means to be the Mother of God." Luther's Works, 21:326, cf. 21:346.
I wouldn’t necessarily go by what Luther said, especially a snippet.
As I said, evangelicals believe Jesus is God, and as He came to earth and took human form, Mary was His mother in that sense. It is the stated Catholic belief as well. There is no problem with “Mother of God” in that sense.
The trouble comes in in all sorts of other places where Catholicism rejects other Christian doctrines to give Mary and her human relationship to Jesus, and His birth, an undue place. There’s a focusing on things that’s misplaced.
Yes, she’s unique in a way. But the really important thing is the Spirit of God through Jesus coming to live within a person, so that they, who were spiritually dead, become spiritually alive. In that way, we also have God living within us.
Catholicism makes her so unique, that she’s isolated. She’s not a person of the Trinity, but she’s not like anyone else in the Church, when I think that she is in some ways is true, and that would be just what spiritually she would and does want, the fellowship of equals among other creatures. The Bible descriptions of her show she felt that way. I also think that what Catholics would burden her with, if it were possible, no person would want to be burdened with as they are the burdens of God Himself. The Bible teaches that if in obedience to God we surrender ourselves He will give us what truly fulfills us, and that means what God created us to be, even if we don’t in the beginning see ourselves as we really are. If we are more or less than we should be, as God made us to be, we can’t have true spiritual contentment. At the end of the day, Mary knew that she was Jesus’ mother in many ways that were not like the God the Father and God the Son relationship.