Sorry but I can’t get excited about casebacks, they are the part of the watch you don’t see whilst wearing it so they contribute very little to the wearing experience.
With my repairers head on, they can be an absolute pain to refinish when damaged from clumsy attempts to open the watch. They’re surprisingly difficult to refinish correctly, re- doing the straight grained finish on some us always a challenge. Concentric graining is easier but difficult to get an even finish.
Definitely the least significant aspect of a watch for me, although I do like the Seamaster logo on 60s Omegas. The gold insert on the 60s Constellations is also pleasing and its a good way to assess how hard a life the watch has had!
Glass/display casebacks......... total waste of time for me, when I’ve finished working on a movement I’m sick of the sight of it! I seriously don’t see the appeal.