I think you're heavily over-estimating the need for Stamina mate. You could easily drop all the Sta from gems (get Piercing gems for blue sockets if you really want the bonuses), I'd recommend switching at least one enchant (shoulder/legs) to the agi/crit version and get 500agi on Bracers (feel free to change on fights where you take heavy spike dmg, like Ji-kun). Expertise enchant on gloves and blurred speed on boots
Considering you wont be replacing your staff for a long time, consider the investment to get Dancing Steel.
You're using Glyph of Fae Silence, can I ask why? I would personally never advise this, but I don't know your raid comp and maybe you're absolutely required to get another interrupt on Horridon or whatever, but you shouldn't really use this because of the incurred CD on FF. Mangle > Lacerate > FF > Lacerate > Mangle again should be your 'normal' priority, highest chance to get Mangle procs for inc rage gen.
Just a few observations ^^