I prefer slab for the same reason. It's easier to clean. I was raised by a mom who was always modern/contemporary. She could immediately point to ANY piece of furniture and tell you how much time would be wasted on dusting/cleaning. Shaker would be as far as it goes and never, ever white in the kitchen lol. I lean toward modern/contemporary. I think that has a lot to do with preferring slab cabinets. However, as an artist and someone tuned into aesthetics with literally EVERYTHING, I think it also depends on the amount of cabinets and whether they will be in an open vs enclosed space. The more ornate, the bigger the space should be I would think. And for a super clean look not only slab fronts but drawers instead of cabinets for which I'm inclined also. Just be sure to have longer, more visible but varied hardware or suffer a sea of white or almond or wood. I'm seeing more kitchens with mostley drawers and am soooo happy. The convenience of pulling out a 4 ft deep drawer to see ALL of my pots and pans at once. Stand back and scan your home as you walk into or face your kitchen and picture what color, and what pattern. I know what I'd do with a big kitchen. I'd split the difference. I'd do a different color and slab front bottoms with lots of drawers and have shaker uppers. Or if I had a flush wall of cabinets that houses a fridge and ovens. If there are a lot of uppers, make sure some have patterned glass to break it up or just open shelves (dusting always).

Dropping it down 3/4 should do it. I would install a piece of 1x4 above the track, flush with the front of the jamb. Paint it, then install the door track toward the front of the opening. Add a piece of 1/4 round molding in front of the track if necessary.

I have a 36" stock bifold door on a bedroom closet. Stiles are 2" wide. Top is 4.5" high and bottom is 8.25" high. These are one panel shaker doors. The stiles look a little skinny but are ok. They would probably be a good width for a narrower door. I used a cabinet knob. My 22" 5 panel doors (custom designed by the door company) have 3.75" rails in the middle, 4.25" stiles on knob side, 4.5" stiles on hinge side. They look thick. If you figure 2/3 of that, yours might be 2.5" in the middle and close to 3" on stiles. So I would say 2-3" on stiles and middle rails. Larger top rail, and even larger bottom rail. If you are matching other shaker doors in the house, take those into consideration, especially for top and bottom rails. But if you are using standard doorknobs, you need at least 4.25" stiles for the knobs to not look crowded. That only gives you about 3/4" distance from the panel. That only leaves 6" of panel compared to 9" of stile. That would look off to me. My five panel doors have about 9" of stile to 11" of panel, and it still looks thick. I think you need to have skinnier stiles and use cabinet knobs. Looking back at your design, I think you can go bigger on top and bottom rails if you want. That may satisfy your need for bigger stiles. You might be able to go slightly bigger on stiles and middle rails too. Make sure you have enough panel. As is, it looks more like cabinet doors to me than closet doors. Here is my five panel door. If you are doing only 3 panels, I would play with wider middle rails, but no wider than the stile width. (Sorry so blurry.)

1) Regarding the screws.... For the drawer faces: Pocket holes should be drilled into the face frames if they must be attached permanently vs using the hardware to keep them on. The pocket holes should have covers attached (either the plastic or wood options). I personally prefer if they are removable via removal of the hardware so they can be changed out or refaced in the future & since you're going the custom route I'd defiantly want it! Inside the cabinets: A pilot hole should be drilled prior to screw if the wood hardness requires it & the screw counter sunk (slightly below the side walls) with or without plastic caps (depending on the company). Cabinet/Wall Brace:Are all the cabinets secured to the wall with simple screws?? I was really surprised to see this! How are they making sure the bases are secured to studs & not just drilled through into the gypsum board? In the past I've seen cabinet makers use a base board across the run anchored into wall studs and the bases are then secured to the board. Holes: The hole that will be exposed once the dishwasher is installed needs to be fixed. The fridge cabinet with the double screws and the blank hole is ridiculous...whomever was doing the install rushed and didn't care about screw placement or taking the time to properly aline things before drilling. Again= Custom built should = quality control and care! Yes there are MUCH better ways of finding the studs...even just using your knuckles to knock on the wall can get you close enough that a max of 2 holes might need drilled if you miss it the first time....again, sloppy work installing. The range microwave: Did they know that cabinet was going to support a microwave/hood? I'd ask about the install and max weight support. I don't believe 2 screws is enough to hold it (especially if they only screwed it into the wall & not a support board!) but don't know...I'd just hate to have it come crashing down a year from now! *You need to make sure the cabinet makers know that screw placement & finish result is important to you and you expect no screws will be felt or seen once the install is complete. 2) Shims: Yes, it's totally normal for wood shims to be left under the cabinets. Floors aren't completely level and in a new build the house will settle over time and the floor will change so it's important that the cabinets can be leveled. This is why RTA cabinets like IKEA have adjustable feet on the base that's hidden with a toe kick. Custom cabinet makers use wood shims to level on site during install and those can then be removed or added to as time goes on and any changes are required to keep the cabinets level. 3) Fixture & Outlet Holes: Yes, it's common to have large square pre-cut from the backs before install as plumbing is different for every job & since fixtures change depending on the choices made in faucet, garbage disposal, dishwasher lines, etc they can't make exact cuts. Again, this is why a lot of RTA cabinets are backless and if the backing is ordered it must be cut by the installer to fit the existing fixture spaces. HOWEVER- I totally agree with your being upset about the range plug placement and their solution to cut another hole into the side of the custom cabinet boxes. Although- I'm not entirely sure I understand correctly if it had to go through another base to reach the outlet or just the base of that unit vs the back side where a hole was already cut? I don't know what another solution would have been.... 4) Cabinet Face Gaps: Are you doing a full overlay with the new build as well? I completely agree that the gap's should be consistent and you definitely shouldn't be able to see the contents of the drawers! If the cabinets are full overlay why is the frame not hiding the contents? If they are custom inset then I'd be very picky about how it all lines up since this is a fine craft that requires skill & time to get right (hence the excessive cost)...plus wood swells & contracts so they need to fit properly with a slight consistent gap after install.