I decided to go ahead and add some of the backstitching to the lighthouse, and I love how just that little bit adds the definition that was needed.
Fingers crossed that the additional skein of Caron Collection Wildflowers (Fir) that I had to order won’t be significantly different from the one I have used so far. Nowhere in the instructions did it say that I would need more than one skein of each color used, but as I was beginning to work across the top clouds/sky section, I began to suspect I would run out before finishing. I have a couple of short strands left, but that will probably be used for blending the old to the new, if needed (and if possible).