Thanks to everyone who participated in the poll and provided comments. I’ve decided to go with Robert Abbet’s John Carter of Mars after all. I think the arguments were all well presented and I’m confident this is a good choice. Here is the final version which incorporates some minor changes based upon some of the notes that came in. I’ve fixed the color balance so that it matches the rest of the frame better, and have done some tweaks to make the title easier to read.
I also worked Abbet’s Thuvia — my second choice — into the back cover of the book, so for those who prefer that one, it’s there, or at least the Abbet is there, on the back.