Our cottage kitchen base cabinets are Ikea but we're using a local company for the uppers to allow more customization. I have a concept drawing from the KD and for the most part I like it. One (second picture) wall is completely without uppers and I would like opinions if the shelves should be on that wall as well.

Your space is gorgeous. Since you don't need the extra storage, I would keep it very simple and place a few black-framed prints on those shelves. You can go black and white or use pop of color, vary the sizes, and overlap them to add interest. I'd also mix in a little greenery and wood elements, like a couple oversized cutting boards, to warm it up and tie in with your floors.

My original plan was to paint the lower cabinets a slate grey/blue and the uppers white. This is opinion, but I dislike mismatched cabinets, especially in a small kitchen. I’m adding a light coloured quartz countertop with a waterfall edge at the end of the peninsula. No, a waterfall edge is a modern finish, and that doens't match what you have -- not unless you're making a huge change in the whole house. The floor will be LVT in a light wood and the new appliances stainless. Good choice; stainless will lighten up the space. I’m wondering about the one upper cabinet to the left off the sink. It only holds the plates and I can fit them in the corner cabinet. The upper part of that cabinet is hard to get into so I rarely put anything in there. Now I’m thinking I should remove that cabinet and put a couple of open shelves in that spot. In that case maybe all the cabinets should be grey/blue since there will be so few of them? I'd keep the cabinet. It already exists /is already installed, and closed cabinets hold much more than open shelves. With the dining table so close, do you use the stools at the peninsula? The stools were the first thing I noticed. They're too cramped for practical use; that is, no one could get out of, say, the second stool without disturbing the others. Downsize to two workable stools. After all, you have the table right there. Other thoughts: - The window needs a curtain -- this is an opportunity to bring in color and pattern. - The pendant lights are on the small side. The one above the kitchen sink is really too small. - The items sitting on top of the cabinets don't look intentional (except the red pot on the dish cabinet, and it needs to sit on a little cardboard box to increase its height + it needs friends). If you're not replacing the upper cabinets, I'd add pretty (matched) baskets to fill in this space -- choose wide baskets so you can still store these items. This will also camoflague the odd box created by the oven vent.

I would simply do a nice long cabinet thta fitsunder the window and if liucky spans the whole with of the wall. It will give you aton of closed storage and then add a couple of items on top that you love and maybe a light.