I disagree, no one is looking down at the captain except tactical, and I imagine they're mostly listening to the captain and looking at their station or the view screen. Everyone is level with each other. Even so, the center chair is distinct and undeniable. And I love love love the command bench/bank/whatever with the captain's chair flanked by the top two advisors, each with their own consoles, and each of those flanked with additional seating for additional crew and visitors. It's downright regal.To be fair it's only elevated enough so that everyone's not looking down on their captain. And you could also ask why the guy at Ops is staring down Tomalak.
The stations at the back don't seem to actually be necessary for whatever is happening in the actual episodes. I imagine them to just be extra work stations, almost like in the early bridge concept art with the couches and so on.
But the idea of the D bridge is that they've automated ship's functions enough that a minimal crew could run the bridge, if not the entire ship being run from the captain's chair armrests.
Also, everyone looks up to their captain, wherever they may be.

Facts.(Let's face it, everyone's looking at Andreas Katsulas when he comes on screen no matter what direction their console is facing).