Poetry is all nouns and verbs.
I don't see that a single line can constitute a stanza, although it can constitute a whole poem.
Prose is not so dependent on sound. The line of poetry, with the breaking of the line - to me, sound is the kind of doorway into poetry. And my sense of sound, or my ability to control it, lapsed or grew less.
A poem in form still has to have voice, gesture, a sense of discovery, a metaphoric connection, as any poetry does.
Poetry takes place in time. It is a durational. Things take place in sequence.
Marvin Bell always looked very closely at how lines could break, how you could put over one line into the second line. How you could stop the line two or three times within the line: You could make it stop.
Poetry is its own medium; it's very different than writing prose. Poetry can talk in an imagistic sense, it has particular ways of catching an environment.
One characteristic of modern poetry is that arrangement of parts which strikes many people as being violent or obscure.