Dont underestimate left tree LMB, right tree is very over rated stacking poison is not difficult. The dps increase from left tree is very strong. The main reason assassins are having trouble stacking poison fast is because they arent making use of acid star (6 second cd poison stack tool that gives focus…. use it pls…). Being able to proc acid star efficiently lets you spec into left tree easily. Also having enough crit for the double venom slash stack does wonders. TLDR go left if you have the crit rate and if you play assassin well enough for constant acid star procs.
Also your argument for choke bomb > poison breath is flawed. Yes you can dps sooner by having the instant poison stacks from choke bomb and start using your dark strikes with Best BNS Gold Store. But casting dark strikes a second earlier is gonna make you deal more dps then having your 5 stacks 15 seconds earlier? Pretty much makes no sense at all to ever take choke bomb over poison breath in PVE.
Cyclone Sweep is another point i dont agree with. Shadow drain for the extra focus regen allows for more dps because you wont run into focus problems, lightning rod wont always be up and the best part about shadow drain is that its cd can be reduced.
But the point that actually makes me question life is shuriken?? Really?