You seem to have a lot of symmetrical pieces.  A lot of manufacturers are producing balls with high-end covers on symmetrical cores.  I personally don't like asymmetrical cores and thus I stay with symmetrical.

For an event like team trials, I feel the more important thing is to have a well rounded arsenal where you have defined steps you know work when going between balls.  Having a plan of attack for different patterns and having the ability to make changes to your plan as needed is important.  Having equipment that meets as many of those demands as possible is more important than having the hookingest ball on the market.

I would take the equipment you have now and experiment on the shots from last year's trials to get an idea of what you need.  The shots will not be too much different this year.  Experiment with surfaces and angles of attack to determine what you need instead of what you want.

I wish you the best of luck!