Diane, you completely missed the golden age of adult films. They used to have an actual budget, with multiple cameras, etc. The sex sometimes was almost incidental, but always there.
Classic Films:
1. Private Teacher - with Kay Parker, Honey Wilder, and Tom Byron. This one is every guy's fantasy.
2. Surrender in Paradise - with Ginger Lynn, Jerry Butler. Filmed in Hawaii, I think.
3. Felicia - my wife's favorite - with Rebecca Brooke. Actually filmed on a villa in France.
4. Aunt Peg's Fulfilment - with Juliet Anderson.