She looks much better with the back stitching.
I wasn't thinking though and now I realize that linen was likely not the best choice of fabric to use for a quilt block. I have decided to do a second block, this time on Aida. This one has lots of stitching also but no back stitches and it is composed entirely of whole stitches. I'll see how it progresses.
Thank you to those of you who have contacted Sharon and have offered to do a bock or two.
If anyone wants to send me a photo of her finished square I will happily post it here to share with our fellow cross stitchers.