I think you'd be better off going with a red room and decorating with navy curtains and bedskirt, or vice versa, paint the room blue and then accent with red. My room has been painted red for about 10 years and I loved it! I'm ready for a change now, but, I really liked the coziness and atmosphere of the red. If he wants red, I'd let him have red and break the red up with blue and white. Whenver I see an accent wall I think the person decorating the room chickened out from what they really wanted to do. IMO, the blue is a little powdery. It might not have as much depth as you'd like to see in a blue paint. I like the concept of red and blue though! My son's room is painted yellow and has red and blue accents. It lends itself to Americana accents very well.

cozy/homey warm *IS* yellow. I don't mean Duck Yellow, I mean if u want a warm feeling, that's what a YELLOW CAST gives u, now u have to decide how much yellow on the brown, if that's what u like. Green and Yellow crash I believe, and I don't feel warm with green, but the walls are only part of your kitchen. Your floor is warm, you counter top with the brown splotches is warm, and u got brown trims on the caps, so now u gotta decide whether that's warm enough for u and some green wall to complement is gonna do the trick. That and how much natural lighting u want/available in the space and even color of your proposed lighting. In general: Yellow = warm Blue = cold Natural light (blue) = cold Artificial and warm white lights = warm Intenser color = cozyness, Neutral light color = opens, airy. There is a science to this I believe, but am not gone that far ahead myself. Hope I didn't make it more complicated for u! :)

You know what will help? Inspiration images. Start collecting images of kitchens you like and it will give you an idea of what you’re looking for. You’re going to change the backsplash too, yes? Also, if you want to move the sink out of the corner, now’ s the time.

In my opinion the requisite gray needs something to brighten it up and the elephant ear/gauntlet gray seem to dull it out rather than complementing it. I think either a white cabinet (no yellow tones in it) would make it looks nice along with more colorful accessories, or a warmer brighter color. I would google requisite gray (maybe add on kitchen) or look for photos on Pinterest or facebook for inspiration. There are also lots of great webpages by professionals online, such as this one which can help guide you: https://www.rughdesign.com/color-selector/requisite-gray-sw-7023-complmentary-palette/ Good luck!