i have the same character but different build.. same recharge battle standard traps idea though.. one thing i noticed is pre-ragnarok, it's very hard to equip if your stats are str+dex, i had to sacrifice some resists.. but with all these OP ragnarok items, it's possible now.. i had to sacrifice DA but whenever I'm under battle standard, I'm ok.. i still like it better than high DA but low recharge.. of course that means you have to play more carefully because if you forget to cast battle standard, you become squishy.. one thing i can guarantee: 3 pet jewelries (physical), and you won't need poison.. most of the time i don't even need to attack.. it's different from other trappers like illusionist because you usually throw traps away from you, but with assassin you cast traps near you so they get under battle standard.. battle standard gives high 200+ flat physical damage to traps and throwing knife and those are both rapid multi attacks
if you have marbod's mask and archmages clasp, it becomes easy to gear.. but if you have some of those OP ragnarok items, it's possible even without those 2.. I'll take a look at my toon in a few hours
edit: you need some cast speed for this build