I’m always a fan of textured rugs like sisals, especially in a dark room with a lot of texture. I also love the antique patina of a Persian rug. Stay away from small, tight, precious patterns in favour of more geometric, larger-scale ones. They’ll look great with caramel leather club chairs. For your sofa, I’m imagining a dark grey velvet sectional. You mentioned that you have two black dogs, so you’ll want to stay away from light furniture, and velvet has a way of staying luminous and inviting because of the way it reflects light, even in a dark colour.