The Emperor sitting upon the Eagle Throne in the Basilica Nova.
The Basilica Nova, which may or may not be revealed (you spies and traitors of the empire! Barbarians!) was the site of the first Imperial Court. It gradually became a temporary Senate, and when the senate moved out for a massive renovation of the Basilica, they never returned, having constructed their own opulent structure during the 200 year process. It sat in the heart of Nova Roma, and was thus known as the Basilica Nova. Years later, the Emperor officially proclaimed the Basilica as his "workplace," and it was shut off from visitors except for a few select days each year. The tall, cavernous basilica was fitted with stained glass windows, and four Gothic "cathedrals" were quite literally stuck on the four sides of the Basilica, leading into it's center. They weren't really cathedrals, just ornate, expansive hallways leading in.
Anyways, enough of my rambling on, this is just a vignette. An idea for a possibly larger throne with a crazier stained glass pattern.
A note: This is the Emperor portrayed in his "around the house" armor... He wears a large battlesuit when going to war.