The new Catalyst cell with tonics, Engineer with pylons, Zeal, and Aetheric Attunement are all good choices. You may change the +3 Utility cell in the Lantern to whatever u wish.
If Surgical Precision has no cap, and is broken aF, cunning, discipline, and attack speed may actually be decent choices to slot in due to the multiplicative returns, whereas %damage would have highly diminishing returns. The strategy I will be running is to have 1-2 Pike mains wound all parts while 2-3 Striker mains break them with +6 Savagery slotted in.
U may also swap out Wild Frenzy, Evasive Fury, or Berserker to slot in +6 Savagery if u have a Pike main in your team wounding all the parts. I am not sure if Aetherhunter will be META or not, based on that, one may change Aetherhunter to Ragehunter in these builds. Unless they make some drastic changes to balancing or something that went unnoticed on my part, these are the builds I will be using for Umbral Escalation.