t's important to consider the fundamental differences between poetry as a spoken form and lyrics as a sung form.
I think your analysis is an excellent one. I think the setting of poetry not originally meant for song is tricky and rarely succesful (outside of classical music where composers do things to metre and scansion not allowed to The Rest Of Us). One of the few exceptions is the poetry of Rudyard Kipling, which has been set successfully many times over the years. The reason why is instructive. It seems that when writing a poem Kipling almost always had a tune in mind, usually a popular song, sometimes quite banal (Home Sweet Home and the like). The result is the words of the poems have all the characteristics that make them easy to fit to a tune and easy to sing once so fitted.
Maybe in the case of the poems already written by AS he could try and adapt them in a similar way and then try to fit original tunes to them.
"Sir, more than kisses, letters mingle souls" - John Donne
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