I mentioned this several times in the past, but with the lack of content in this game I felt inclined to brainstorm ideas to make the gameplay more fun. Note that this is not all inclusive; these are key features that would be a fundamental part of the job if implemented.

Damage Spells:

True Stone (X potency earth damage on target) 2.5 second cast, Cost 1600 MP
Quake II (X potency earth damage on target and surrounding targets; applies stun) 2.5 second cast, Cost 1600 MP
True Water (X potency water damage on target; replenishes 2500 mana) 2.5 second cast
Flood II (X potency water damage on target and surrounding targets; replenishes 2500 mana; applies stun) 2.5 second cast
True Aero (X potency wind damage on target and X potency over time) Instant cast, Cost 400 MP
Tornado (X potency wind damage on target and surrounding targets and X potency over time; ineffective if target is under effects of True Aero) Instant cast, Cost 400 MP

These are your main damage spells. My rationale for this was for a simple Black Mage-esque gameplay loop where you refresh your dot (Tornado not overwriting True Aero being a QOL feature for mob pulls), use earth for damage and water for damage and mana replenishment.

Holy (X potency unaspected damage on target and X% less on surrounding targets; costs 1 Sundrop) Instant Cast
Afflatus Misery (Now replenishes 2500 mana upon casting; deals unaspected damage potency of x4 True Water)

Holy is just Glare IV with some tweaks. Afflatus Misery will be the equivalent of x4 True Waters to keep WHM neutral when having to interrupt their general rotation to heal. x4 True Stone potency would just incentivize them to use lilies solely for damage.

Healing Spells:

Lily Spells now replenish 2500 MP upon use
Tetragrammaton (Increased heal potency)
Divine Benison (Merged with Aquaveil; 500 potency shield, 15% damage mitigation; 30 second CD; 2 Charges)
Cure II (Naturally evolves from Cure I)

In case of scenario where WHM has no more lilies and still needs to spot heal. This will help ensure they aren't helpless when caught starting water phase. Tetra is there in case Misery is ready so WHM can weave it in for spot healing or to use with lilies. Divine Benison merged to avoid button bloat and give WHM some solid mitigation to compete with AST. Increase heal potencies of most if not all heal GCDs to be higher than AST. Lowering MP cost of healing spells can also help WHM avoid being caught with their pants down.

Utility Spells:

Consecration (Create circular area around self; increases cast/recast speed and auto attack speed by 15%)
Assize (Fully restore MP)
Thin Air (Next three spells that have a cast time will cast instantly; 2 charges)
Presence of Mind (Grants 1 Sundrop)
Aetherial Shift (Unchanged)
Return (Available when Consecration is active; Teleport to Consecration)

Plays into WHM's stationary gameplay. Assize being something to replenish MP should be fine with a more GCD heavy playstyle along with potency increases to compensate. Thin air changed to give more movement for the more bullet-hell mechanics being given to us.

Traits:

Light of Hope (Next Raise spell cast will be instant and cost no mana; 3 charges; passively replenishes over time)
Sacred Sight (Given when the WHM casts any damaging or healing spell; increases magic damage and healing potency by X% for X seconds)
Sundrop (Allows casting of Holy; granted when Sacred Sight is held for X seconds; 3 charges)

The first trait will help Raise play nice with WHM's mana economy/burst window in the event they need to pick someone up. It also makes sense for their identity since they are the healiest healers so naturally they would be the best at rezzing. Sacred Sight is basically Enochian with a paint job. I figured with the DT changes to it--it would translate well to WHM since they would get it by simply playing the game. No Astral/Umbral mechanics with it since they still need to be ready to heal at a moment's notice. Sundrop is then given when it is held similar to Polyglot.

Rotation:

Opener: True Aero, weave Presence of Mind + Consecration; 6x True Stone; Holy, weave Assize; 6x True Stone; True Aero

General: Swap between True Stone and True Water, refresh True Aero as needed. Use Holy, Thin Air and Swiftcast as needed for movement/weaving. Use Lilies as needed for movement/healing/weaving. Use Aetherial Shift and Return as needed for movement.