Looking back I'm not sure the Oxygen theme has aged particularly well
Well, I am currently using the Oxygen theme (with a GTK 3 version called Oxygen SCSS) and I like it a lot better than the default Breeze theme. Buttons that look like buttons, a nice glow effect when highlighting things, and some of the icons* I find absolutely gorgeous (the Log Out, Restart, and Shut Down icons, for instance, have this nice glassy look).
* https://iconarchive.com/show/oxygen-icons-by-oxygen-icons.or...