If you must paint, I say match a dark shade from the pavers, or the grey of the trim and arbor.

Although I agree with Beth; it looks nice as is and some plants would really help to soften the look. You could bring the colour over to the arbor with Terra cotta planters!

thanks, it is a wood deck

having used a deck stain/paint, it's a pain to keep looking nice. even though the can says 5 years, it rarely lasts one year. I would wait until this starts to look faded and chipped and then change the color. Since you have the worst color to cover, it would be best to wait until it wears a bit. Then do a good pressure washing before re-coating it with something else. I do know with those stains, you can get them tinted almost any color. since your house is white, I like the idea of a nice, bold color.

It will look great to match the gray stain of the window trims but go darker and stay in the same family of gray