Lack of closeups

presumably this was to concentrate on the sets and costume design, which are luscious, and possibly, although I'm stretching here, to emulate Roman friezes and bas-reliefs? Actually there are close-ups but not many, and it is tiresome after a while to see almost everything in wide-angle. Where there are close-ups seems to be where dramatic effect is most necessary, such as the scene where Demetrius prays next to the comatose Lucia and remembers the Crucifixion. It works, but I could have done with a few more variations of shot throughout the film

There are more close-ups in Demetrius than in The Robe. I'm yet to see a 1954 CinemaScope film that features many close-ups, however by 1955 things were different - East of Eden, for example, contains many.

The early Bausch & Lomb CinemaScope lenses are to blame. Directors and cameramen hated the fact that they couldn't do closeups, due to the limitations of the lenses. Eventually, the technology got better, and Panavision made far superior lenses and they eventually replaced the original B&L's.
There's a great website about widescreen movies with detailed tech info and a history of it's development . Do a google search of "widescreen movies" to find the site.