I have two ideas for course set up and design. I totally agree that a longer course is not any more enjoyable - and yes I have the length and game to shoot sub-80 rounds on 7000 yard courses. Here are my thoughts.
1) If the course has 2 sets of tees, one for women, juniors, and seniors at about 6000 yards and one for men at 6500. There is no need to have longer tees unless it was designed for pros to be playing on it.
2) If the course has 1 tee box, with the hazards and bunkers not starting until about 250 where only long hitters and pros would be affected. It may seem unfair for the women, juniors, and seniors, but that is what the handicap system is for; and it may seem mentally tasking for women, juniors, and seniors to shoot double bogeys or worse on every hole, but what really matters is the final score with the handicap. The handicap would adjust for the scores they would shoot. Remember that in the Open championship that they always announce the scores as the total number of strokes, not how many over or under they are. After adding the handicap, women, juniors, and seniors would have scores that would as closely resemble the way they played compared to the mens' scores.