Had not noticed this post when it first appeared, Sunbug, likely because it landed amid the holiday swirl (so much disappears into the vortex that stretches from mid-December through the first week of the New Year), but you raise a fascinating point.
I’d add to your list the Homeric hymns to Hermes, Aphrodite, and the other Olympians, not to mention the Psalms of scripture, and the tales of the troubadours (aka Minnesingers, in German) of the Middle Ages, which were performed as song.
Rhythm preceded the emergence of speech for our early ancestors – and once language did appear, rhythm, along with the repetition of formulaic phrases (e.g., “the wine-dark sea” and “there spoke clever Odysseus in Homer) made it easier to memorize lengthy, epic tales told around the communal campfire and passed down from one generation to the next.
David Abrams (in his elegant volume, The Spell of the Sensuous: Perception and Language in a More-Than-Human World 101-109), notes that Homer may well have been an oral bard, or rhapsode (from the Greek rhapsoidein – “to stitch a song together”), those who sing the myths; drawing on a rich oral tapestry of traditional stories and formulaic phrases, and stitching them together in performance – which would explain how he could be blind and still create these detailed epics in verse). Indeed, the Iliad and Odyssey are composed in dactyl hexameter, which has much in common with the rhythm of modern rap.
Forgive my rhapsodizing about the resonance between the rhythms of rhapsodes and rap – but the connection between myth and music (both of which are associated with the realm of the Muses) is worth exploring.