As your floor color is deep, carpet should choose some low brightness, high saturation color. Your study is big, you can choose pure wool carpet, its characteristics are long fiber, tensile, elastic, shiny, slightly coarse fiber and powerful, and quality is enough. Sticking with floor is the plastic carpet.
This kind of blanket generally does not appear in such a situation, or coffee color and black, generally use hard materials, dark red
If you are afraid that the stool leg damages the carpet, you can choose floor with cloth pad, there are also patterns, it's very nice. Pure wool won't stick with floor no matter how to step and use, it doesn't need much money, they do, do the actual laying is good