Depends what your style is but something with texture and seems like you like monochromatic tones? 9x12 and 8x10? You can use different rugs asling as they relate to one another.

A good place to start is to find rug dealers in your area and visit the stores in person. Most rug dealers will allow you to bring a rug home to try out and some will even let you pick several rugs in the store and they will then bring them all out to your house to compare. I've never felt pressured to buy any of the rugs when I didn't find one I really like when I tested them out in my home. Just part of doing business and establishing a relationship with customers.

You might consider doing some simple rugs with maybe some texture. Below are some images of rugs we have used in our designs.

Simply High Line · More Info

Southampton Modern Farmhouse · More Info

Southampton Modern Farmhouse · More Info

Contemporary Weekend Delight · More Info