Are you thinking of doing wood directly behind the range? That would be a huge fire hazard and against code. If you were to incorporate boards, you would need to pull off your window trim, then replace and the outlet boxes will need to be pulled forward (should be enough slack in the wiring). But, imo, I think you need to skip the boards - and do tile. I haven't been reading any of your threads on this - have you considered tiling that entire wall (to the ceiling and to each end of the wall)?

I used laminam in the kitchen for back splashes. I didn't want anything that had grout or uneven surfaces that would be hard to clean from cooking splashes and spills. My husband juices a lot and you would never know it. I used the cream color and it looks beautiful. Best of all, after four years, it's as clean as the day it was installed. It's very easy to clean and everything wipes right off. The sheets are very large and thin and have to be handled very carefully. Our cabinet builders installed it for us. It was the first time they had even heard of it but they were impressed. We are building a new home and will be using it again.

You certainly won't be needing your display cabinet in the new house. If you have lots of stuff to store but not to display, you might simply frost the glass doors to hide what's inside. Or do you have enough books to fill it up? The smaller one could be turned into a dry bar, or you could add a wine fridge underneath and do a wine bar. If you don't imbibe but love coffee, make it a coffee bar. Personally, I would replace the diagonal wood with drywall and go ahead with flooring. I see that same wood is installed behind the cabinets, so you could salvage some of it to close off the upper openings entirely, and just let that wall feature a bit of the wood since you love it. I hope you plan to remove the ugly valance over the sliders. Look for a big area rug that both of your leggy sofas can sit entirely on for good grounding. Only 12-18" of flooring has to show around the perimeter if you want to go really big with a colorful, patterned rug, or you could just have broadloom bound as well.

Please post pictures of the doors and your space. Usually the easy answer is paint them the same as the walls but in a satin finish.