I think in terms of style, rather than right or wrong, I prefer "Go either right or left," or better yet (for emphasis) "Either go left or go right". It goes back to 8th grade English, diagramming sentences. Either is a fork in the road, and each tine needs its own go to achieve the parallelism that is, IMO, facilitative of understanding. Highly subjective, mind you. I have only my audacity, humility, and good looks to back it up.
As to the original question regarding "Dismiss not passion or grace or thoughtful concern," I think it would be acceptable to use
Dismiss neither passion, grace, nor thoughtful concern.
The main reason for this is that it sounds good to me, and as you know, IISFTTHWI. I direct prescriptivists to Merriam-Webster, who comment
usage Although use with or is neither archaic nor wrong, neither is usually followed by nor. A few commentators think that neither must be limited in reference to two, but reference to more than two has been quite common since the 17th century <rigid enforcement of antique decorum will help neither language, literature, nor literati -- James Sledd>.
