I think that Funcom needs to make Test Center more of a testing server rather than another server.
What I mean by that, is we all have characters on RK1 or RK2 that we spend time building up. We dont' want to have to spend time building up another character on TC.
We should be able to /petition a GM on TC to change our level. Let us test out different classes and different levels quickly. It will let us test out what IP combos to use as well. It will also let us test out changes for high level characters without spending the weeks it takes to get there.
UO had a great system where you walked through a portal and it raised your skills to a certain level instantly. Terminals like that on the TC would really help out if the Gms don't want to constantly go around altering characters.
Also...put the test center as an option for logging in. Make it simple and easy to use. The more complex and time consuming it takes, the less people will want to experiment with it.