Try lots of pure white with one or two accent walls of midnight blue (or dark grey). Mix in some hot-yellow accents and you're done!

I can't seem to figure out how to get a great picture of a tongue and groove living room that also has ceiling molding, off of one of my houzz ideabooks to show you that this style you like, can and does look good together. I picked the collaborate feature and put your user name in it to try and share this pic.

Moss. Preferably the thick dense dark green kind of moss that looks like a carpet that grows on the north side of embankments where little sun reaches. How close is your nearest state or national forest or, in the alternative, the nearest dirt road with an embankment that gets little if any sun because of shade trees. Take a drive and/or walk and see what kinds of moss you can find and take some pics. A dozen or so pieces would likely be all you need to get it started because, with the right conditions -- shade and moisture -- it spreads. (Ferns like shade but usually do better with drainage. Moss likes damp but will not grow in a puddle.) Where you have windows, you could create a "view" : With a concrete planter (or on concrete pavers set a large clay planter) with a trellis with English ivy. Alternately, you could buy your own pieces of exterior grade plywood and use deck screws to affix them to the fence posts and horizontal supports of the fence and decorate them w/paint and/or planters and/or metal sculpted art --- get creative.

Have a look at Dulux 50GY 45/037 or Colortrend AP5-6 Folkstone, as a possible alternatives. Just note that low Chroma, near neutral colours from the Green-Yellow Hue Family can shift blue in imbalanced light. Less likely when used outside.