go to etsy and look up wire wrapped jewelry 61k items, silver smithed jewelry 1500 pieces. Just about every Craft store has wire wrapping lessons some several times a year. As far as polished backs I'm sure they would prefer them in certain instances probably most of the time, there are those that would probably like the grooved cabs, cabs drilled for bead like things and it goes on and on there is a huge market out there presently being cornered by the Chinese bead factories and low cost low quality mass produced cabochons. just saying. This is kinda hijacking this thread so I'll quit now
No please keep going. I had no idea the wire wrap people were so plentiful. The more information the better. On the 90° angle domes do they prefer a rounded top edge or sharper?