You have plenty of room! Do a console under the mirror and a cool upholstered bench on the other side. What is your style, maybe posting pics of other rooms in your house would give us an idea what you like so we can suggest pieces :)

Attached are pics of my living room and kitchen!

console under mirror and bench on other side for sure. you can always get a ruggable rug which is washable. for an indoor outdoor rug that van be hosed off outside. you're going to need something to wipe your feet and paws on.

I would get a colorful Oriental rug in polypropylene, which is easy to clean. That large an area without something soft and colorful underfoot will not look welcoming, no matter what else you decide to put there. Look at carpets that have rust red and blue colors in them. An Oriental carpet will look good with your mirror I think.