Ancestral Warchief (3 Questions)

I'm attempting to figure out how to optimize this build I'm using.
I'm working on an Ancestrial Warchief build that uses Atziri's Disfavor.

My 6L: Ancestral Warchief, Faster Attacks, Melee Physical Damage, Reduced Duration, Melee damage on full life, poison.

Passive Tree: goo.gl/TBc4d7

Question 1: Would using reduced duration not be a good idea as it would affect the length of the poison applied to the target?

Question 2: Is the full hit converted to poison damage or only a portion of it? and should I replace this gem with perhaps conc affect or in aoe.

Question 3: I plan to use belly of the beast and scale life rather than armor to save a lot of points and apply it to damage instead, is this a good idea?

That would be it! Thanks!

1. rapid decay is better then less duration if u go poison.
2. 8% of the combined physical and chaos damage dealt by the hit is ur poison dmg. Replace Melee damage on full life with inc aoe/conc ...
3. Belly gives u %. Tree gives u %. Belly is good if u have lot of life on ur gear, if u dont u dont have life to scale. So, Kaom heart is best because u get 200% (or something like that from tree) from 500 life.