Once complete my gearing for my build it will be using Undaunted Infiltrator 5 set, Spawn of Mephala 2 set, and the Poisonous Serpent 3 set. At the moment I have the full set of Undaunted Infiltrator and use Molten Armaments and/or Degeneration (mages guild) to trigger it's buff. It's truly hard hitting damage, with my bow heavy attacks landing well in excess of 10k damage against vet delve bosses. The key to my method of Bow heavy attack DPS in PvE is to keep up my DOT's (Scotched Earth, Poison Injection, Eruption, Burning Breath, Unstable Flame, and Degeneration) to keep the damage ticking while I'm charging up the heavies.

Buffing bow damage truly comes from focusing on critical rate and critical damage in addition to your physical damage. It's actually a fair trade off from regeneration and bigger stamina pool gearing options if you really focus on heavy attacks, as they'll restore healthy chunks of your stamina. Focus on using Earthen Heart abilities and consider using Evil Hunter to further extend that stamina bar, but always always always prioritise your DOTs.