Since you still have time. I'm going to tell you to go PB build right now. Get PB to level 28 or you're stuck at MP3 until level 78-ish.
As for the other skill to neglect, keep MP Eater at 3 and Max out Slow.
This way, when your PB is 28, you can switch to training on Jesters, which is pretty fast. And can help you get the idea of Misting during 3rd job.