C-Case's were probably the start of a new era for Omega where they didn't produce the same dial again and instead made at least 1 change to it - my theory is the Quartz collapse happened later on and the creativity wave died, I don't know of any other model where they did this
SMDV's have more variety in dials, I didn't pay attention but if their base models also have small changes it would be a nice pattern and maybe can enter the knowledgebase as an approach for that period