Infinite Hysteria. Swap weapons while in Hysteria and farm energy off of [Hunter Adrenaline] when running low on Energy. It doesn't make sense to run Arcane Energize since you won't be needing to actually pick up any Energy. Arcane Grace and Arcane [Guardian] just allow you to easily farm Energy off of [Hunter Adrenaline] without having to really worry about dying at all.

Efficiency is still better than Duration for [Valkyr] as well. If Efficiency is maxed, Power Duration does not matter whatsoever. However, if Efficiency is below its maximum then Hysteria relies completely on Power Duration.