Appreciated. I never liked shingles anyhow.

I plan to build a two story (one and a half story?) cottage of stone masonry walls, the upper level will be the 'bonus area' of the attic. So, the roof will most likely be steeply pitched, or have a compound-pitch like many barns, to maximize upper level space. Is one superior to the other, insofar as insulation, weatherproofing, and durability? (durability concerning storms, high wind, heavy snow, etc)

At any rate, keeping the rooms in the upper level from turning into solar ovens is crucial, they will be living spaces. Any suggestions on accomplishing this?

There are two possible locations.

The first one would be here in the rockies. High elevation, semi-arid desert, not much rain aside from the summer afternoon thunder shower (high intensity but short duration. There are very few 24-hour rainstorms or longer), winter snow accumulation can pile up to 3 feet on the ground, more than that is rare and the average is more like a foot at a time. Lows in the winter nights are in the single digits to teens. Highs in the summer are upper nineties. Humidity is generally between 30-50%, usually hovering in the low 40's, mid 30's. Wind is generally mild, most days have light breeze and frequently we see 15-20mph fronts coming in, it would be newsworthy if the winds picked up faster than 35mph here. Generally the sun is bright and clear, more stark at these elevations and clean air.

The second location would be in the southeast, ozarks or Cumberland mountains. Rainfall is more regular, humidity is around 60-80%, snow accumulation is less than a foot during the occasional storm. Ice storms must be considered and can place an inch or more of solid ice on the roof, which is equivalent in weight to a foot of standing snow, yet presents other complications as well. Temperatures range from winter night lows of the mid teens to summer highs of low 90's, with less fluctuation between night and day than the previous more arid climate. Wind is even more mild due to the foliage cover and the height of the house. Sunlight is somewhat muted by high thin cloud cover and humidity.

"This home has stainless steel windows also...."

Must make for a very boring view, eh? Nice and shady inside though.

I've heard spray-on-foam and other non-ventillated insulation traps the heat in the roof layer, which, depending on what it's made of, is generally detrimental to it's longevity?

The roof will house a 'bonus area' like a second level of the house. two bedrooms and a small bathroom. It will not be airspace and rafters, or at least, not nearly as much as a conventional 'empty' attic space.

Sounds like metal is the way to go. How about insulation? What are some good options for this configuration?

what about a rock cave???