Thanks lwo. I am waiting for my carpenter to do the installation and he will have a stud finder so we will know at that time whether he needs to beef up the wall. But I have a recollection from when the vanity was installed that it was not screwed in under the sink because of the lack of a stud. The dreaded drywall seam hump is why I would like to avoid have to do drywall work on that wall - you are right that it will affect how the cabinet sits against the wall.

I recessed a medicine cabinet that was 'supposed' to be wall mounted, just framed for it and shimmed plumb and screwed into predrilled and countersunk holes, similar to window installation. Then I used joint compound over the screws and painted it. Then I drywalled up to the edge of it and caulked around it then painted to finish it out. Inside of my cabinet was white so it was easy to just paint white where needed, would be harder with a wood finish, possibly just leave the fasteners visible. Has to be installed during framing and take thickness of the drywall into account when recessing.

Not that I have one--but since it's not structural, you should be able to use 1/4" material on the back, there's 3/4" or whatever wallboard on the other side. Then, if you look at the topmost pic with the doors, you can see that the doors & trim are proud of the wall itself--level with the base trim. So not as much loss as you are talking about. Equally, looks like about the depth of a can of tuna--so somewhere in the 3-3.5" range from the pictures... I do find shallow is incredibly useful for pantries because you can see everything...

With bringing the whole 12" trim plus crown across the pantry bump out to the corner, my worry is that the "crown" part will overlap the window casing in the top left corner. Similar like you old cabinets' crown to the right of the window did in the photo above. I don't know, maybe it is the photo angle, but I'm just having a hard time picturing it not hitting. Based on the two example photos of the built up crown above, it looks like at least half of it is the crown piece that starts to protrude out. The top of the window trim looks too high for that large of a crown to not hit. Here is a thought. what if you removed the window trim altogether and just have tile around it with no wood trim. It would give you more of the "whole wall of tile" effect. Normally, I would want all the windows to match trim, but since the top line of the kitchen window looks to be the only one that is placed up higher then the rest in the next room, it might actually look planned. It would cost a bit more in tile and labor, but should not be a crazy amount. You could try removing the trim for free right now just to get a feel for if you would like it or not. Then maybe add a piece of cardboard or whatever to mimick the 12" trim and the 6" or so that sticks out to make sure it clears the corner. Try it both with or without trim to see what works best. Right now your kitchen is pretty traditional looking, but I think it will lean more transitional once you paint the cabinets, add new light fixtures, and especially once you add that very modern looking chimney style hood. It going to be great! I couldn't find a good example of the tiled in window next to a SS chimney hood, but here's sort of what I was picturing for the tiled window look. Thoughts? :-)