I keep looking at the 'Coptic' design £1.88 value Christmas stamp and wondering if it is just my view or whether, indeed, Mary's hand is wrong. Jesus' fingers are a bit strange too but that doesn't trouble me too much. The artist, Fadi Mikhail, who created this image using ancient techniques and did so specifically for this issue, mentions in a recent interview, published in the November British Philatelic Bulletin, that it is very difficult to correct errors. Perhaps that explains it.
Below I illustrate a similar pose on another stamp which, to me, is much more naturally angled.