Hi there,
A 10x7 rug can work really well in a medium to large living room, depending on your furniture arrangement. A good rule of thumb is to have at least the front legs of your sofa and chairs on the rug. This helps the space feel cohesive.
If you want a more “floating” look, you can place the rug entirely under the coffee table, leaving a border of floor visible around it. For style, patterns that aren’t too busy can help the room feel balanced, and neutral or muted tones make it easier to match with different furniture.