For the fireplace inserts go ahead and do the green order a second set of panels that you store that are more neutral. In 10 years or five years you may not like the green anymore. It's possible you won't have access to different colored panels at that time. As for the color I like the ideas of going into those silvers it would coordinate very well with your blue couch and it will pull the blues out of the curtain panels. For the wall coloring use the warm golden color in the drape. There is one piece of the flower that has this color and it will balance the weight of a dark couch. If your room is small don't go too dark in this color. You could use it on the main wall and pick two shades lighter on the other three walls.

Oh so cool you noticed that we're trying to achieve a french country/industrial look or did we write that somewhere? I've attached some other photos of a bedroom and the foyer (of those we've taken so far), but are absolutely open to suggestions on a "beachy" feel as well or instead of. Although because its a beach house we don't want to go over board on expense and hence keeping what we already have, and just adding personality to it, if you get what we mean. Kingsize Black upholstered headboard to come in that bedroom.

Deep gray and all the other accents in silvery old wood and cream. This will add drama, allow the other elements to bring ion light and set off the concrete wall as a true feature. If you want light instead of drama, then go for a very pale beige stone. It will echo stone colours in both the concrete and rocks...

It looks like you have wallpaper on the wall behind the sofa. am I right? How many walls are you painting? Post more pictures of the space if you can. My inclination would be to go deeper like BM normandy, black pepper, taos taupe, iron mountain… but hard to say with seeing so little of the actual space.