> For example, how many houses have a cupola? They're common on older homes, but non-existent on modern ones. What the roof does is accelerate the wind moving over the roof, then the air vents in the cupola let the wind through, which sucks the heat out of the attic.

This one is genuinely obsolete. With modern techniques, it’s straightforward to build a reliable unvented attic, and there are few if any climates where a vented attic makes sense. There are plenty of climates where a vented attic, even a nice one with a cupola, is massively inferior to an unvented, conditioned attic.

Seal and condition your attic. Put on a decorative cupola if you like. If you live in a place with heavy snow load, you vent a small gap between the top of your attic and your roof surface to help keep the actual roof surface cold enough to avoid melting the snow.