I would kill for the ability to warp text along any sort of path. (GIMP probably has it, but I haven't explored it much, and for this particular challenge I was test-driving Pixelmator. Which may well have it, I just don't know.) So I ended up not doing anything to the text and just using the warp tool on a texture I had created out of a failed ink painting. (I figured even if the painting was no good, the background was interesting and could be recycled.)