Currently , once a user have SetPriority access ,he can select from Low, Medium, High or Critical priority levels to ensure certain jobs always take priority over others.
This feature can be misused as users can upgrade their priority levels to jump up the queue and later downgrade the levels. It's difficult to justify and ask each others when you have 1000+ jobs running in a day and it makes administration tough and gives unbiased Gallery to all end users.
It would be nice to have on Admin console, global option to set max priority level so that no user can jump up level beyond this.