Intellect > Haste > Mastery > Versatility > Critical Strike
Intellect > Critical Strike to 24% > Haste > Mastery > Versatility > Critical Strike beyond 24%
Intellect > Haste > Versatility > Critical Strike > Mastery
Also Avenging Crusader is unaffected by Mastery, if you talent into it mastery becomes your lowest priority stat.
Critical Strike: Chance for each attack and ability to do twice as much damage or healing.
Mastery: (Mastery: Lightbringer) Increases the healing you do based on how close your target is to you.
Versatility: Increases damage and healing done and decreases damage taken.
Races are a minor thing, and all of them are viable.
Tauren: Gives you an AoE Stun with War Stomp, primarily sees use in PvP. Brawn buffs your critical strike healing by 2% and synergises with Holy Shock. And it gives you Endurance which provides you with extra Stamina.
Dwarf: Stoneform Removes all harmful Poison, Disease, Curse, Magic, and Bleed effects and reduces all physical damage taken by 10% for 8 sec. this is an additional defensive cooldown and sees a lot of play in High Mythic+.
Human: Will to Survive - Removes all stun effects. And The Human Spirit, where you gain 2% more of all secondary stats from all sources.
Dark Iron Dwarf: Fireblood is like Stoneform from Dwarf, but you get primary stats instead of the physical damage reduction.
Draenei: Gives you Gift of the Naaru, which can be good in some situations.
But you should choose what you like best and what fits the best for the content you play since the impact is minor.
Enchant Weapon - Sophic Devotion
Enchant Chest - Waking Stats
Enchant Boots - Plainsrunner’s Breeze
Enchant Ring - Devotion of Haste
(Avoidance enchants mainly for Mythic+)
Fierce Illimited Diamond - +75 Primary Stat and +66 Haste
Haste: Quick Ysemerald - +88 Haste
Haste/Mastery: Keen Ysemerald +70 Haste and +33 Mastery
Mastery: Fractured Neltharite + 88 Mastery
Mastery/Haste: Keen Neltharite +70 Mastery and +33 Haste
Haste/Vers: Energized Ysemerald +70 Haste and + 33 Versatility
You will use 1 Fierce Gem and then a mix between Haste and Haste/Mastery Gems depending on your stats.
Phial of Elemental Chaos which gives you following effects rotating every 60 seconds.
Elemental Chaos: Fire - Critical Strike increased by 652. Damage dealt by critical strikes increased by 2%.
Elemental Chaos: Earth - Mastery increased by 652. Damage taken reduced by 5%
Elemental Chaos: Air - Haste increased by 652. Movement speed increased by 10%
Elemental Chaos: Frost - Versatility increased by 652. Healing dealt by critical strikes increased by 2%
Sizzling Seafood Medley which gives you 67 Haste and Mastery
Potion of Chilled Clarity is a good option when you know, you would burn a lot of mana in that 15 seconds window.
Potion of Frozen Focus is the channel potion we know from previous expansions.
Elemental Potion of Ultimate Power gives you primary stat and could be used if you don’t have mana issues and boost your healing or damage.
Aerated Mana Potion normal instant restore mana potion.
Howling Rune Imbue your weapon with the energy of a Bakar, increasing Haste by 707 for 2 hours
Refreshing Healing Potion this could save your life in a raid encounter.