Based on your picture, looks like you lean towards neutrals vs bold or busy patterns so thought you might like something similar to below.

If you want pattern and more interest, the accessories will accomplish that.

An idea if you want more color.

If you want to stay neutral, your current rug looks pretty good. however, you might benefit from bringing in an accent color, which could appear in the pattern of the rug, a throw pillow or two, and some other accents around the room, to pull it all together.

I’d choose a blue patterned rug. I see you have a blue armchair. Blues and cool grays like your sofa look great together.

Is something like this too bright/busy for you? I think red-toned rugs can look really nice with gray, and your built-ins look like they have a blue tone. There's also the option to a smaller busy rug on top of a larger jute or sisal rug.

Included here are a few rug ideas from designs we have completed for clients.

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