A truly beautiful color (or - value, I might say...) is gray. It's a timeless classic that goes with so much, and so many styles.
If you prefer modern elements in your design - you could opt for the minimal 'bare' idea using the deep browns of natural woods - coupled with the contrasting 'metal' feel of gray. It's an underused and beautiful combination. Since this style often uses natural woods with heavy wood patterns, it's best to stick with a solid color gray cowhide rug to add a splash of gray to your minimal, modern space.
Or, maybe your wood does not have strong grains - in which case the gray brindle cowhide rug is quite stunning as well.
There is still yet another option - that would work well in a traditional style design, minimal or modern - or just about any living or bedroom space - and that is the larger (for larger area) is the gray and brown patchwork cowhide area rug.
All three of these options offer versatility with the design and offer warmth, nature and design elements when used in a design.