You'll have to excuse my ignorance, I'm just not to sure, isn't changing to Underworld and Bali altering the GTK theme? I use Breeze Dark, then Underworld, Bali's Black, and still playing with different icons. Currently Griffin Ghost is my choice, plus the high contrast cursor.
Oh, I see, ya that's a bit above my pay grade. I just got a setup which looks clean and stuck with it lol. But let me know what your think of the layout!