That's an excellent point about attic venting. It's amazing how hot an attic can get. That heat gets radiated down into the room below, too, as well as doing all the nasty things you described.
When I had my new roof put on last year the contractor added multiple ridge vents and soffits vents.
My attic temperature is much lower and I know that will be reflected in the temperature of the house as the summer heat rises.
Not that it gets that hot here on the coast.