The 3" cabinet does sound like it would look silly, not be very functional, and cost a lot because you would pay a premium for those pieces.

A OTR MW isn't anchored on the sides anyway. The mounting plate goes on the back wall and is screwed into the cabinet above. Why not just put a piece of trim on the side of the MW mounting plate to hide the metal and leave everything else alone.

Umm, why can't you get a 6" wide upper pullout over your 6" wide lower cabinet or pullout?

I think sometimes it is a code thing about ranges next to doorways. We had this in a 1926 house we used to have. The range was next to the back door. When we redid the kitchen we slid the range to the right and placed a 9" tray cabinet on the right -- that was about a 10" piece of countertop that actually turned out to be useful. But it doesn't sound like you have that much space. Can your KD do you a mock-up of how it would look?

bmorepanic: KD was changing out the 6" to a 3" on each side, to surround MW (and I suppose the left lower one as a buffer with stove/doorway)
jakabedy: mock-up was done...it looks thin (shocking, huh?) but it's hard to tell from a mock-up if it only looks thin or if it looks ridiculous! I'm going to ask KD if it's been done before and maybe ask for pictures. I really, really want to get MW off counter. Maybe KD fed into my desperation? LOL
Also will ask granite people if they've ever done a 4" 'countertop'. Their reaction might just show me the way.

Try this:
http://www.frigodesign.com/php/essentials/microwave.php

I meant to add that you can then use this somewhere else other than over your mw.

I know this isn't exactly what you asked, but you may find it helpful.

Our kitchen before our remodel had a slide in range, and had smallish, maybe 4x4 or 5x5 tile squares for the counter top.

The odd layout of the range led to a rim of tile around the back and one side of it that was about 3-4 inches. I hated this.

It was JUST too small to put on a glass or small plate, but guess what....thats just what people would do . This drove me crazy. If it had been 8 inches or more, it would probably been fine. But as it was it was nuts.

OTOH, I just did a google image search, and found 0 images of range and microwaves that had the range at the end of a run of counters.

If you like the range where it is, and the problem is the micro-hood, then could you do a range and downdraft ventilation, and do an upper horizontal box cabinet to hold a standard microwave?

After an exhaustive search on FKB, small kitchens, I found Devi's Kitchen which has the exact set-up my KD was talking about! One of her pictures shows the wall box surrounding the MW and on another I can just about see the very narrow base box by the side of her stove. So my KD wasn't just making this up...it's actually been done so maybe not such a bad idea.
Of course Devi's pictures are from 2005 so I doubt she's on this forum too often now but hopefully there's an e-mail address and I'll try to contact her!