Monk is bar none my favorite class in WoW. These are the changes I would love to see.
Mistweaver
Soothing Mist: Revert to Legion Functionality
Effuse: Return from legion
Vivify: Revert to Legion Functionality
Uplift: 2 Charges, heals all targets with renewing mist for small amount and trigger gusts of mist on each target healed.
Enveloping Mist: Causes gusts of mist to trigger twice. (Like essence font)
Sheilun’s Gift: Bring back, clouds of mist form each time you trigger gusts of mist. Tune healing accordingly.
Invoke Chi-Ji: Off the global cooldown
Stance of the Wise Serpent: Improve raw healing spells.
Stance of the Spirited Crane: Trigger eminence in some form for fistweaving.
Windwalker
Serenity: Now replaces Storm, Earth and Fire as primary baseline cooldown.
Storm, Earth and Fire: Perhaps revert to WoD functionality.
Strike of the Windlord: Bring back from legion, feels great with serenity.
New Spell: Seven Sided Strike (from diablo 3 monk, it would be perfect with serenity)
New Spell: Exploding Palm - This could act kind of like soul reaper on DKs, on a short cooldown, dealing damage over time. If target dies or is under 35% health, explode dealing damage to all nearby enemies. Perhaps upgrade talent could allow it to spread to nearby enemies like living bomb. Could synergize with touch of death for some cool combo aoe burst.
Tigereye Brew: I would be interested to see this brought back as an alternative to Serenity. Perhaps charges could regenerate out of combat?
Mastery: Hit Combo - Revert to Legion Functionality
Brewmaster
Chi: Bring back Chi as a secondary resource. Remove brew cooldown interaction.
Ironskin Brew: Stagger additional/all damage for a short duration. Costs 2 Chi. Shares a cooldown with purifying brew. 3 charges. (Specifically without the brew cdr so it’s an interesting choice)
Keg Toss: Bring back from WoD/MoP
Choose One: Chi wave or Chi Burst
Chi wave: Consumes all Chi, creating a Chi Wave for each Chi consumed. (This would look fantastic)
Chi Burst: 1 Chi, regular effect, 2 Chi, increased Range, 3 Chi, Heal for each enemy hit, 4 Chi, Purify Stagger Damage for each enemy hit, 5 Chi, Chi Burst Returns to monk after travelling full distance. (Something to this effect)
Blackout Kick: Now blackout strike, costs 1 chi, triggers shuffle, increasing dodge by 10% for 6 seconds.
Keg Smash: Generates 2 chi. 2 charges.
Breath of Fire: Costs 2 chi.
Spinning Crane Kick: Costs energy, generates 1 chi. Perhaps increase parry chance while active.
New Passive: Dodging or parrying an attack has a chance to make your next chi consuming spell cost no chi and cast at maximum effect.
Blackout Combo: Blackout strike empowers your next chi consuming spell.
Purifying brew heals for some of the damage purified over time.
Ironskin brew pauses all stagger damage for it’s duration.
Breath of Fire heals for each target hit.
Chi wave bounces 2 additional times.
Chi Burst explodes upon hitting an enemy, instantly triggering it’s effects twice in an area. (Chi Explosion)
Exploding Keg: Change to simply reduce enemy damage dealt like demoralizing shout.
That’s my wishlist. A bit of a mix between Legion and WoD primarily, with some of the current iteration and a couple of new things mixed in.