I only just now realized that there are slight differences in design between the weapons in the Row IV art. Like the harps in the Elysion art: there's more strings on Gran's harp, the silver part on the top is slightly different, Djeeta's harp is a bit more curvy, and the gold-ish thing near the bottom of the harp is completely different.
The new Class Champion weapons seem to mostly be the versions from Gran's art, save from Apsaras, Nighthound, Warlock, and possibly Spartan's weapons. I can't really tell the difference in Spartan's case.