Post by Josren
I would say the Trinket is an excellent choice, I love mine, and to be frank, it will give you more AP when its all charged up than your JC trinket. The belt is a solid upgrade as well, but so are your T10 pieces, so take that as you will. I will suggest placing the 21 crit, 3% crit damage gem into your headpiece instead of the minor run speed one. As for hit rating, once you hit 17% spell hit, anything over that is better taken up by Haste/AP/Crit, etc.
EnhSim is a program used to simulate your gear, rotation etc. on a static boss fight, over an extended period of time, giving you a DPS that is more or less achievable, barring movement and such. It's helpful for tweaking your priority, gems, and such to eek out the most DPS.http://elitistjerks.com/f79/t82621-enhsim_updated_thread/
Check there for links, and the latest updates to the program.