I think the brick helps warm it up. I would add a living wall on one of the brick walls as well as planters at the corner and next to seating. If the ground color is really bothering you a larger rug would help.

Also, that floor would be easy to paint -- use a sanded exterior paint in a lighter khaki shade or pale gray or whatever you want! would leave the brick though.

just realized these didn't get attached previously ;-)

If you own, then paint the brick but not too bright. It will be blinding in the daylight. But I really like the brick as is. Plants tall and whispy. TSP on hands and knees each and every paver on your floor. Let it dry. Do this early in the morning while cool, then let the sun do it's thing. Next day, when the sun is NOT on the balcony, stain it. Rustoleum has stain kits. about $60 per kit. Not knowing the square footage, one kit may do just fine. It will take about a 3 day weekend to do the job, but worth it. And it keeps the green stuff off the patio in the end of winter months. I liked the terra cotta color for my patio, but it may be too much for your balcony with brick. You'll have to see if the hardware store or paint store (Kelly Moore) can get you a different color. http://www.rustoleum.com/product-catalog/consumer-brands/concrete-stain/concrete-stain-kit . Look for videos on youtube. Oh, pop of color on your sofa, such as a multi color throw or smaller pillows, or school logo/mascot even. The rug is stunning, maybe a white ceramic barrel table for the side as well or a white ceramic statue of animal for fun.