According to a GE cooktop installation guide, they recommend a minimum 30" vertical clearance to combustible material and/or metal cabinets. They also state that if this isn't possible, a 24" clearance may be used if "the underside of the cabinets over the cooktop [is] protected with [no less] than a 1/4" insulating millboard, covered by sheet metal no less than 0.0122" thick."

I'm hoping to do something like that. I'm going to try having the mw in the corner area first - if that doesn't seem to work out then if/when I redo the kitchen i'm thinking of putting my oven 'up' a bit at the end of the cab run (see first pic below taken of a dw set up at my local Lowe's) - with the mw setting on top of it. and when I saw cotehele's cabinet on here I saw what I think I want over the mw and going up the wall - the right side of her cabinet shown below. She has what looks like a little toaster oven/mw on it also. I think I'd want glass doors on the top part for a display area. It would be rather similar to what is actually over the dw set up at lowe's. cotehele's cabinet

As Alku05 mentioned, a WD really needs to be very close to the cooktop/range to be used regularly. If you have to traipse across the kitchen to use it, you probably won't use it that often...or so others here have discovered. I had also planned your setup, but after reading others' experiences, I moved it to the cabinet to the left of my cooktop. (Later, we changed to a double oven, but that had nothing to do with the WD placement.) Even though we've only been using our kitchen a few weeks, I have already thanked the wisdom of this forum for this advice...I use it quite a bit. As to MW, I don't think it will be a problem--especially if you move the WD elsewhere. But, I question the location of it in relation to the sink & refrigerator. I don't know your layout, but keep in mind that most MW'd food comes from the refrigerator or freezer for reheating or cooking, with some water added. So one of the better locations for a MW is next to or very close to the refrigerator...which in turn brings up the recommendation that both the refrigerator & MW be on the periphery, but still in, the kitchen. This allows snackers to raid the refrigerator or use the MW without interfering with work being done in the kitchen. One last question...do you have landing space to the left or right of the proposed oven cabinet? Immediately to the left or right is ideal, but a couple of feet will work if you have no choice. Landing space in front of it will also work, within 4'. I know this is more than you asked, but I wanted to share what I've learned during my almost 1 year on this site! My kitchen is so great directly b/c of this forum...all the ideas, advice, and help! Please, avail yourself to the many people here who are happy to help! In the end, though, remember this is your kitchen and it should work for you and your family and how you use it! Good luck!

@acm I hadn’t thought about into the sunroom then out the side. That would be easiest, but would mean two bends. I’ll have to look into that. For wall cab plans, If you can make out my very hastily (not to scale) drawing. We have one hanging cabinet planned between our front door and window and an easy reach corner wall cabinet (the kind that wraps around corner, not angled) in the corner next to the range. The picture with the MW on the metal shelf is where that first wall cabinet would be and I agree that is the best spot. I’ve liked it there. It’s very accessible, you have a place to set things when you take them out. Its close to my cooking area but not right in it. This morning I told DH we absolutely could not hang a MW under the corner cabinet. It’s such a bad spot. You can’t actually get in front of things in that corner. I can’t imagine trying to pull hot things out of a MW from to the left or right of it. That does sound dangerous. He has agreed to put it in the wall cabinet that corresponds to where I have it now, but only if it can be inside the cabinet. The cabinets are shaker but he is definitely throwing in some craftsman elements and he really wants to try to get that uniform look that you see in craftsman furniture. This has been really hard because our space is odd and in order to make it work symmetry has had to go out the window. He is wanting to try to make the uppers as uniform as possible. I’ve done lots of sketching trying to figure out how things will work. Here is one when I was trying to imagine how to make the microwave not look completely out of place there above the range ending at the window. I just could not do that to my satisfaction. A hood will not only be more functional but it will look so much nicer in that spot. Here I adjusted a drawing to make the wall cabinet have an open shelf for the MW. He doesn’t like how that it would make our only two wall cabinets no longer match in style, which I get. I’m not super excited about the idea of having to open a door to use the microwave, but I’ll do if I have to. I’ll work on him some more first and see if I can get him to come around to either an open shelf or a built in. GE does have a smallish MW that can be built in or hung and would fit on that shelf and we decided to make them slightly deeper to accommodate a MW more easily. Since our prep areas are under the windows the deeper cabinets won’t affect us. I could hang it under the cabinet but then I’d have to move my coffee pots and I really like them there. @kaseki I hadn't thought to try that, though the MW is currently in a box. I was going to call GE however since its been decided to put the MW in the wall cabinet, no need to figure it out I’ll just sell the MW. Thanks for the tip about wind direction. I’ll keep that in mind.