Stat Priorities
Stat Ranking
In every situation:
Intellect > Haste > Mastery > Versa = Crit
Item level is almost always going to determine if the piece is an upgrade regardless of stats; however simming your own character will always be the best option when deciding whether an item is an upgrade.
Stat Outline
Haste makes it so you cast your spells faster, reduce the CD of Conflagrate, and increase Immolate's tick rate. This is why haste is our best secondary stat.
Mastery is just passive damage increase and has gained some value due to the talent Chaos Incarnate.
Critical Strike increases the chance of your spells dealing a critical chance. Crit also gives Chaos Bolt more damage. It provides 1% damage per 1% crit to it.
Versatility is just a passive damage increase and passive damage reduction stat.
The best way to calculate stat priorities for your character is to "sim" your character.
Races
All races offer very small dps differences but if you are trying to be 100% optimal:
The best race for the horde is Orc followed by Troll and Goblin.
For alliance it’s a Mechagnome followed by Gnome, Dwarf, and Human.
Enchants
Rings: Devotion of Haste or Devotion of Mastery or Devotion of Critical Strike (please sim)
Legs: Frozen Spellthread
Feet: Plainsrunner’s Breeze
Chest: Waking Stats
Cloak: Graceful Avoidance
Wrist: Devotion of Avoidance
Weapon: Wafting Devotion or Sophic Devotion (please sim)
Gems
In Dragonflight, there has been an introduction to primary stat + secondary stat gems. You can only have one of those equipped at a time. For warlocks, the best gems are Fierce Illlimited Diamond followed by Keen Ysmerald. (please sim)
Consumables
For Phial, Iced Phial of Corrupting Rage is the best simming option, but consider Tepid Phial of Versatility on some bosses where you can’t get high uptime on the corrupting rage phial or for high M+ dungeons.
DPS Potion: Elemental Potion of Elemental Power / Elemental potion of ultimate power
Healing Potion: Dreamwalker's Healing Potion
Rune: Howling Rune
Augment rune: Draconic Augment Rune