One on top of the other? Ummmm…no.

Your husband is right for wanting proper ventilation, and microwaves are inefficient at best, and downright lousy in reality.

Show us what your kitchen looks like, and the good folks here will make suggestions for placement of the mw. So, step back and snap a pic of the entire kitchen.

I have a wide galley kitchen, and did this:

The vent hood microwave combination was designed for builders that want to save money by buying one appliance that solves two requirements. If you truly want a custom kitchen, and don’t want to have to reach over a hot range to get things in and out of the microwave, and have a Venthood that really works, use a vent hood for venting and put your microwave someplace else. When we’re designing kitchens we analyze how often they use the microwave and what they use it for. If you use it all the time you want it within a good reach. If you’re an occasional user then you can do things like the drawer microwave down below. If you have a wall oven then the obvious choice is to put it right on top of the wall oven.

The pictures of the design are above. Edmond KItchen adn bath. I don't understand your comment "If you have a wall oven then the obvious choice is to put it right on top of the wall oven." So where would the vent be? I am a little confused?

Pictures make a difference! You have a slide in range rather than a wall oven so disregard that. But when you put the microwave over the range, it’s no fun to use. Know that most microwaves are deeper than your 12 inch deep wall cabinets so if you put it where you have it drawn in this drawing that cabinet will bump out a bit.

I have an idea book of microwave solutions I have gathered. But it basically comes down to on a shelf in the cabinet run, microwave drawer, and on the countertop. I personally like in the cabinet run dropped down 3 inches.

We have this small Whirlpool and love it. https://www.whirlpool.com/kitchen/cooking/microwaves/countertop/p.0.5-cu.-ft.-countertop-microwave-with-add-30-seconds-option.wmc20005yw.html?