Here's the skill build I have in my guide:
1 Flash Jump, 1 Sudden Attack, 1 Vampire
5 Claw Mastery, 6 Booster
30 Critical Throw (max)
19 Vampire (max)
15 Mastery (max)
9 Sudden Attack (max)
19 Haste (max)
14 Booster (max) OR some mix of Booster and Flash Jump
You only end up with 1 FJ, unfortunately.
Vampire is an awesome skill, you don't want to be missing out on a whole hunk of damage for not maxing Mastery. Crit is pretty much a neccesity for raising Vampire though, it raises the average damage of Vampire from 30% per hit to 80%.
If you need ideas for 3rd job, you can PM for a link to my enormous guide on all things cygnus, but I don't want to be busted for advertizing a link here.