I am not very keen on these mirrors, I think them useless as a proper functional mirror. May be try them as a decorative object? I am sure you've seen a lot of items decorated in this style, with 3D ornaments, I am always the last one to try! And then I come across this master-class and having the mirror already primed and painted I decided to give it a go! 3D details turned out far from perfect and I highlighted it by adding craquelure and patina. Now it looks like it was made of ivory long-long ago!