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...

Yes benches are counters .... thanks for clarifying yoboseiyo! we have no high cabinets for the kitchen at this stage, we plan to do some kind of shelving but are waiting until the new "counters" and range are installed to get the feel for what we go with. Hard to get a photo at present as we are mid reno, the cabinetry is all installed....with no bench top yet.. we have our old cooker in the dining room and the new big range in there too as the area its going into is being tiled. The range will be the dominant feature in the kitchen so once that and the counter tops are in I'll take some pictures Organised Chaos!

You have lovely pieces to work with. To my mind, it appears you have a long and a short MCM credenza/buffet. I'd prefer them switched and then move the art pieces so they take up no more than 75% of the credenza's length. Also keep them closer to the furniture and lower than the door and window frames if possible. Red is a wonderfully appetizing color and I'd love to see it on the dining room wall as well, although I know it may make the air unit more obvious. The dining wall is the one I'd fill with a bookcase for the cookbooks. As a one-time owner of nearly 100 cookbooks, I found they made for great dinner party conversation, along with an unabridged two-volume set of the English language dictionary. An IKEA bookcase could work well and hold plenty of books. The white shelf system with the red wall behind and the backs of the shelves painted red would look great! Or you can paint the bookcase red and leave the wall white. Group books by color for another touch of fun! Don't forget to show off some great "foodie" accessories too.

Well you posted this several months ago, but I thought I would make suggestions anyway. Hope you don't mind. In order to stay with or keep in mind the style of the shelves I would first change out the towel rack and TP holder to a chrome, or brushed nickel finish. Or get something that goes with the water faucet on the sink. If you are going to paint the wood around the shower base, paint the window trim and pieces of baseboard that are wood as well. I agree with using a gray color that adalisa, above mentioned. Maybe paint your vanity a darker gray, or even a shade of black, like your shelves to tie it in. That's it for me.