Naz'jatar Primer

For Patch 8.2 Day 1 Focus on Naz'jatar* till you hit a wall in story progress and in the process of save all benthic gear(unless duplicates) and all mana pearls.
If you are a crafter(leatherworking, blacksmithing, jewelcrafting, engineering, tailoring, alchemy) your best first investment for your pearls is the anvil(75) unless the quest for powerful items from a vendor still exists for mana pearls(need 20 of said item at 5 mana pealrs per[100 total]).
Youll also encounter a quest for 120 activities in Naz'jatar so that is currently ,unless changed,: Rares, WQ's, Ally Dailies, and Chests which will lead to an essence and further story progression of the zone(more mana pearls and wq's ect).
Your next investment for pearls after the questline or anvil is up to your research for your individual classes.
A few of the essences are tied to pearls so if they are good for you this may be a wise investment or the benthic gear may be your foreseeable BIS in regards to the azerite gear or some of the bonus effects for encounters.
Once you hit a wall in nazjatar your next focus is the Mechagon story line up to the new Mega Dungeon and any available dailies at the main hub for rep.
The Reason for this is once again some essences are tied to mechagon rep as well as the new mega dungeon.
Once all of this is done it is Simply Rinse and repeat WQ's , Dailies, and mana pearl swoops.
*This includes the upgrading of the heart of Azeroth in Silithus as it is actually part of the Naz'jatar story line.