All your photos show veneer- see how the pretty grain patterns continue across multiple cabinets? That is only possible through veneer. You can choose a plywood base or mdf base for the veneer but asking for solid walnut will not get you the look you want and will be more prone to cracking with changes in humidity. Solid walnut would only be available from a full custom local shop.

Yes, you are insane. (You asked.) Veneer is superior to solid. Especially if you want those pretty grain patterns and not a striped pieced together look. Which can be virtually a butcher block type look of appearance if you get lower grade walnut and a cheap cabinet maker taking advantage of someone that doesn't know anything about cabinet construction. Walnut is already expensive enough as a veneer, for custom cabinets that are done well, as your inspirations are. What budget do you have for cabinets? Just cabinets. Not the full 200K upscale kitchen remodel that you are picturing.

Here is your solid, expensive as all get out, walnut.

Our cabinets are solid walnut and the posters

above are correct you will not get that matched grain effect with that only veneers. here are ours. each door is made up of multiple pieces.

Sure, you can have solid walnut doors. You just need the budget for full custom cabinets, plus the budget for the HVAC upgrade to kerp the humidity in your home at a constant level. That means a humidifier add on for the winter, and a dehumidifier and/or AC for summer. No open windows, etc etc.

wsea above shows solid slab doors with well matched boards. It takes a high level craftman to accomplish this. Ech has to be selected from all the available. Not just for integration between boards, but the length position within a longer board. You'll need an experienced furniture maker.

Walnut also has dark heart and light sapwood.

Just saw neighbor's well-done walnut veneer done by skilled cabinetmaker. Simple slab cost nearly $200/linear foot. If you want veneer facing (like your photos) on solid walnut doors, add another $50/ft. A kitchen like that is a work of art... but probably not right for toddler/dog era.

P. S. Are you sure you're not confusing "plywood" with "particle board"?

We are hard on our cabinets (toddlers, dogs, etc) so leery of veneers.

Walnut is one of the softest hardwoods. Even heart pine is harder. If you love the look of walnut slab doors, perhaps look at laminates (HPL's). Some of the laminates are very realistic looking and a better choice for the conditions that you describe.

Upside to laminate is predictability-- what you see is what you get. No color/ grain surprises and the color will not change. Unlike real walnut which actually gets lighter as is ages. Scrubable/ scratch, scuff, dent resistance. Downside is predictability--pattern repeats.

Unless money is no object, solid walnut cabinets are going to be cost prohibitive. We did a walnut veneer for this client with the grain going horizontally, and they're terrific:

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Usually the reason for veneers is the fact that that is a more stable cabinet door that does not move with the changes in humidity. For me there is no such thing as semi custom, they are either custom or not . I think if you already know you are hard on kitchens maybe something not real wood but has the look is the answer like the HPLs .BTW walnut is my fave wood and I use it often for flooring and walnut veneers for cabinets . Toddlers grow and have to learn to not destroy stuff on the way. . As for source there is not way to advise about that without knowing where you are, your budget . My advice is to get an independant KD who has cabinet compnaies and builders they work with and know the products well.

"We are hard on our cabinets (toddlers, dogs, etc) so leery of veneers."

I find it sad that you would buy cabinets in exquisite walnut, knowing that you, your kids, dogs, etc. will be hard on them. Perhaps wait until your next kitchen when your kids are out of the house to get solid walnut kitchen cabinets. Get something durable now, so that you won't have to look at the dings and scratches on such a beautiful expensive wood as walnut. Also, with a busy family, do you really want to be tiptoeing around your cabinetry?

I was always told that solid wood slab cabinet doors warp. If it were a shaker style door, the frame could be made of solid wood and the middle would be made of something more stable, veneered and/or painted.

I guess that’s what others have been saying with regard to the stable humidity requirement.