It really depends on the house and kitchen. We have double oven and a counter top small microwave. Love the double oven. Use it when roasting or baking. Things like sweet potato oven fries in oven #2, while oven #1 does a slow braise. It also works well for baking, things like cookie, can be 4 or 6 pans at a time. Although that tends to create another problem of storing multiple cookie pans.
However the really useful part is having one set up with heavy baking stones for home pizza and breads. The other is used as a regular oven and then your not juggling the heavy stones all the time.