Critical Strike: Critical Strikes give you mana back due to the Resurgence passive and also increased output when you land a crit.
Versatility: Increases your healing and damage by an amount and reduces the damage you take by half of that.
Mastery: Increases your healing done to targets based on their current hp, where the lower their health the more healing you do.
Haste: Unfortunately we don’t have many abilities that scale well with haste, which leaves this stat very lacklustre for now.
In Castle Nathria a lot of the gear is Crit & Mastery so you will want to get a lot of Versatility outside of raid gear.
Pandaren - Gives the most output due to the double effect of the food buff.
Goblin - The Goblin racial ability, Rocket jump, can be very good on certain fights, but i didn’t feel that it makes or breaks any fight in Castle Nathria.
Other than the two above; Troll, Orc, Mag’har Orc and Vulpera are also all viable races for Resto Shaman.
Weapon - Celestial Guidance
Chest - Eternal Bounds
Bracers - Eternal Intellect
Cloak - Fortified Leech
Rings - Tenet of Critical Strike
Crit Gem: Deadly Jewel Cluster
Flask: Spectral Flask of Power
Food: If no feast available use Spinefin Souffle and Fries