I built a long cabinet below the screen area and cut out two of the door panels. So I still have closed door cabinets but two have black speaker material stretched and added behind them. I added loudspeaker material (you can get this on Amazon) - it has worked perfectly for 6 years. (Haven;t got photos here)

Usually when you get side panels you automatically have space on the sides. If you have a full depth cabinet on the top, you automatically have space at the top and in most cases you will have leave at least 1 inch of extra room for the back of the refrigerator, so there is always air circulation since everything is enclosed. In the 70's they use to make a small recessed space behind like Fred said, today you don't have to do that, most Ref have flat backs, recessed wiring, not to mention the supply for ice-maker also comes in a flush mounting kits for the wall... so pretty much everything is recessed and only space you need is for air circulation and 1" is more then enough. In addition, if you make recessed area now and you push ref to far you will never get your doors open so doing all that is a waste of time, in addition most manufacturers starting to make 30" side panels.

I like the room but it looks a bit empty. Possibly some contemporary low interesting cabinet on either side of the fireplace some organic baskets or metal vessels of some sort on top of the cabinets. It will fill in the bareness between cabinet and sconces. Roll down textured shades at the windows would add a nice fill in touch and add privacy and block light. Or simple linen floor to ceiling curtains on rods at ceiling height. Here are three rooms with free standing cabinets and long curtains at the windows. You might like these ideas for not. Art work could be under the scones with lamp for ambient lighting Again simeple cabinets and surprise, a TV stand too. This is a lovely idea too with the twigs; could change seasonally. I like the benches for warmth and texture and softness and the chandelier adds a dramatic touch. Good luck with your lovely room!

Work with someone in your location who designs and provides kitchens. If you location is not in the U.S. cabinets sizes and appliances are very different and info will not apply.