I think that a poem should have literally elements. A meaning deeper than it seems. I think that a poem should have this because the story and the meaning together make the best harmony that only people who seek the truly meaning see.
A poem should not have a pointless poem! Poems are made to tell a story and paint the picture to show the meaning, the soul that this poem that has been created to give it meaning.
I noticed some differences about the Bradstreet poem versus the Williams poems are some as such as these. The most obvious one is that Bradstreet has more writing, more detail. William’s poems have a less meaning. Such as forgiveness, and how one thing depends on the other.
The similarities I’ve seen are that both of them resembled something truth, they have that one thing that has the truth, from the love you have, to the honesty that you have for that person/object.