The problems with that are:
-You have to keep staff later, meaning you have to pay them more.
-You alienate anyone who isn't planning / able to stay till end of the day.
-You eat into the time after park close that engineers have to do daily maintenance to the ride, which could result in more problems the day after.
It does solve some issues that the current set up has, but it creates many many more.
The trouble in the past is that Priority Passes were handed out like water. This year they're more like Coke - still on tap, but hidden away and a lot more restricted.