As much as our friends from Europe bring to the game, the question has to be are Scenarios bringing more fun to more people in their current time and day or would they benefit from a different time and day.
If you put them on a weeknight there is no good time. Later than 9pm starts to be a problem for east coast fliers, while that is but 6pm for the west coasties.
If you move it the best time is Saturday evening.
Also FSOs are going to have more action because they are designed that way. Each frame is set up to ensure a battle, typically 4 locations to defend and 4 to attack for each side. Not all FSOs are historically accurate, but most give the players a good sense of action at that time and location depicted. Which is exactly what they are supposed to do.
A scenario is to be a historically accurate battle (within the bounds of the current gaming engine), with historical units, airfield locations, objectives and all the other tidbits which bring people like HAJO their immersion. A good scenario design ensures that there will be action. A scenario does allow the different sides to make their own decisions on what they hope to accomplish each frame. But good CO with the motivation to maximize the experience for the players (on both sides) can go a long way in a scenario to keep it real and ensure that everyone has a good time. But there are those who let their obsession with winning get in the way of the enjoyment, then you see gaming of the event and everyone suffers.