I love your outside entertaining area. It does need a color that would complement but give the area a focal point. I like the darker red,orange colors you may find in natural. You could dress up the table with accessories and place cushions in a complimentary color on the benches. Colored potting containers would also bring it all together. I like the uplighting here in the photo you could place along the back fence to add drama. Your area reminds me of Modern mediterranean landscaping.

As the appearance of the garden has a modernist style with the straight lines and concrete furniture how about a Mondrian influence and add a bold strip of blue? It is a pond and with the right shade it could look really relaxed and contemporary. My daughter's suggestion is a chalky lilac!

All the suggestions above are perfectly good. However, when you have a house that is entirely painted, the options are so endless that it's easy to get stuck. I'd advise either finding photos of comparable homes in colors that you really love, and reproducing a similar palette on your home… or upload a picture of your house to a colorizing site, and play around with various combos. Sherwin Williams has a Color Visualizer that is decent. I don't mind a white house, but feel that the black trim is a bit harsh. On the railing especially- it feels like it is outlining itself too much. Reduce the contrast between the body and the rail and it will enhance the house rather than overwhelm it. You have a lot of choices, so just experiment and go with what resonates with you.

This just popped up , but I see it is quite old . Did you decide on paint colours ? The roof looks almost a brown tone in the photos , but you say it is dark grey . I assume you don't want to paint that ? If you do , go more charcoal IMO . If you don't , I'm assumimg it will look several shades darker with your wall colour choices . There is a roller door on the garage that appears to be a nice shade of orangey yellow . Personally , I would go with your colour choices , but do all the doors ( roller doors , wooden doors ) and gutterings in that ochre shade . Your terrace I would do in a charcoal , but with the top rail either in the orangey yellow , or a really crisp white . I know that sounds a bit 70's ( although they would have added a lot of ranch brown back then haha ! ) but against the light grey I suspect it would work together well , and look the part .