I tried a new method of finishing the edges, inspired by not having entirely equal strips and needing to piece together small pieces that didn't always stay joined. Except for the neckline, I stitched the strip to the right side of the raw edge and then turned it over to the inside and stitched it in place. Now all the raw edges are on the inside and there is a nice contrast when the shirt is inside out.
And in full disclosure, I was in a hurry to sew this together and didn't have Internet access, so I didn't look up how to prevent the edges from stretching out as I sewed them. It's mostly obvious around the neckline, especially at the back (but not on the mannequin, which has fabric to create friction to keep clothing deceptively in place), which is why this shirt is delegated to at-home-wear only.