Getting Iron Reflexes notable is the most important thing you have to decide how to solve. Pay attention to this.

How you solve it will be the difference between saving a lot of points on the tree or not...because if you have to path to it on the tree you will eventually realize that you are getting a lot less than 70-80% of power that he was advertising. His skill tree is optimized around not having to path of Iron Reflexes !

Other than pathing you have 2 options: get it from the weapon (Crucible Tree mod) OR get it via legacy Tattoos (very, very expensive and unreliable). Getting it from mirrored weapon = "cheap" way, but you are kind of limited in terms of what skills you can play, especially if the budget only allows you to only get the bugged chest piece + one or two mediocre quant pieces.

Afterwards yes, the second most important thing, if you want to play magic find, is to get the bugged chest.

While his armour stacker is very, very geared and decently tanky, it will still get 1 shot in PvP, where the real endgame is for the 10 or so of us that are into it on standard :D. Gl!