When translating verse, I think one should try to capture both the form (meter, line positions, rhyme scheme, etc.) and substance to the extent possible and to the extent not cumbersome* in the new language. "To the extent possible" can require much work that I think is often missing from much translation. I also think the original should be printed on the opposing page so the reader can judge the success for herself.
*Where end stopping or alexandrines, for example, seem cumbersome in English, I would think the original poet would want substitutes that distract less in English. Thus I've often used iambic pentameter in lieu of hexameter. I've also often avoided end stopping where that seemed a distraction (my translation of Phaedre for example).
Here are the English pages of some of my dabblings along these lines. I
think the Veraline & Du Bellay present especially hard challenges
and I keep tweaking......
I. Verlaine: MacIntyre claimed: “No one has ever translated, or can or
will translate [Chanson d'automne]; yet it offers the supreme challenge, the
shifting lure of the bright impossible.” Maybe MacIntyre didn’t try hard
enough?