uhh... They're a pretty complicated class...
One is that they need a certain amount of dex that has to be capped for best damage range overall. Also, STR needs to be implemented since shadowers get shields called khanjar (level 80) and dragon khanjar (120). Both of those shields need STR, which also has to be capped as at certain point
Also, I'm not familiar with the new builds of how a bandit should be post BB, but I would say that when you are questing, you will want to do Alcaster and the Book of Ancients to buy summoning rocks for Shadow Partner in 3rd and 4th job.