I would raise with a bit at a time. Especially the more expensicve seats are prety cost-sensitive. Raising only a small amount will make some diffrence in attendance.
I've been raising ticket prices gradually over the past 3 months, and am happy with the results.
The level of your PR manager will also have effect on the prices you can ask.
They are not your friends; they dispise you. I am the only one you can count on. Trust me.