I have a nice gtk2 / gtk3 theme that mimics sierra. <https://github.com/kencu/myports/tree/master/gnome/gtk-theme-sierra>
For dependencies, if you are using this theme with gtk2, you need gtk2-murrine installed. gtk3 works as is. There aren't too many port themes to copy ideas from. adwaita lists a library dep for gtk3, although it's also for gtk2. if I put depends_lib-append port:gtk2-murrine then that would force everyone to install gtk2. I could registry check for gtk2, and install gtk2-murrine if someone already has gtk2 installed, I guess. But then, if they install gtk2 later, the theme will be broken. Still, perhaps they could figure that out... Or - perhaps best? - just list gtk2, gtk3, ang gtk2-murrine all as lib deps, and install them all. Then nothing can go wrong. Any preferences? Ken PS. by the way, there are lots of themes here for the curious <https://www.gnome-look.org/browse/cat/135/>