Well obviously if your ticket prices are higher, you're going to attract less people. The key is to find that balance that maximizes your profit.
The one thing I've noticed studying arena's is that teams in the same league seem to be far more financially rewarded for builidng more of seats and keeping the price low than less seats at a higher price. And I would imagine this remains true until your arena gets up around 20000 seats.
Of course the downside of that is you have to pay to build those seats but if your goal is to reach the highest division, you're going to have to build them at some point anyways.