For the sake of symmetry, I am considering sacrificing the final verse from the “To a Swallow” draft. I may yet do so—once I assemble the selected variations into a poem and see the effect of the imbalance—but for now, it remains.
The poem has a traditional rhyming scheme: ABAB CDCD EFEF GHGH IJIJ. The asymmetry is created by lines 12 (F2) and 16 (H2) that follow a similar pattern (the repetition of a word set; for example, “Da-dum! Da-dum! Da-dum!”)—an element I want to keep.
I must, therefore, either embrace the “imbalance” for the sake of evocation in lines 12 and 16 or rethink the poem structure (which strikes me as ridiculous) to satisfy my aesthetic inclinations.