The interesting thing to me is that my ranger was built around poison arrow: with Faster projectiles and LMP and Add Chaos damage. Currently I am at +6% damage after the -dmg from LMP and the +dmg from level 13 lmp combined with the +dmg from lvl 13 faster projectiles.
The Tooltip DPS is 1009 dps (rounded)
without LMP it is 1500 Dps (again rounded)
the Dot portion goes from 98 dmg per second with LMP to 122 damage per second without LMP
seems kind of off somewhere. I would assume that given the + percent from the faster projectiles combined with the + percentage from the leveled LMP - the damage reduction from LMP = 6% more damage. would not the damage be a bit better than a 500ish point difference?
Perhaps the tooltip is wrong or perhaps I am figuring the modifiers wrong. Either way I had to lose the LMP because it reduced the damage overall waaaay too much. I ended up replacing it with Lifeleech as I could not justify that big of a drop in direct damage combined with that large of a drop in the DOT portion (which is already marginal).
The DOT portion of Poison Arrow was alright at one point during beta, then it was reduced as someone in GGG felt it was a bit too much. Afterwards the DOT portion was still somewhat okay if a bit marginal at times, now however the DOT seems to be almost an after thought and somewhat difficult for a ranger to improve on. Given that the Rangers starting position there isnt much in the way of +AOE damage or +spell damage
The new base damage of Poison arrow of 78 damage per second at level 13(gem) seems to have gone too far in the wrong direction. I understand that GGG wishs to be cautious regarding this as so many mobs in Act 2 use poison arrow (and probably alot of others in act 3 just reskinned / renamed) however in doing so the players skill is now decidedly inferior for rangers to use without making a fair trek into other area's to get access to + AOE/Spell damage.
Now if this were a DEX/INT skill I could understand it a bit more as being a hybrid skill. However given that it is a pure DEX skill this to my mind puts it firmly in the Ranger zone as a primary skill, with the Ranger being the Pure DEX character. Perhaps I am wrong in this, if so I would like confirmation.
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Before the Patch I could lay down a few poison arrows to build a large cloud then kite around mobs inside the cloud to help kill them. Given the relatively high mana cost of the skill and the prevalence of chaos resist among mobs (high) and the lack of support for it in passives or skills (no chaos penetration support, no effect from concentrated effect, no affect from passive +bow or +projectile damage). Now however it appears that to be usable as a primary skill it appears that the skill will require - reduced cost, concentrated effect (which is elsewhere reported as not affecting it properly though I don't have one currently to test it myself) , faster projectiles, added chaos (for primary damage), thats a 5 socket balance where the stated balance has been claimed by GGG to be 4 socket. This just to be somewhat useable.......
TL:DR = Poison arrow got hit a bit too hard with the nerf bat. Perhaps this needs to be re-looked at regarding balance to bring it back in line with other bow skills