I remember the idea I had prior to shadowbringers for Lilies was to essentially turn them into a greased lightning effect that could be spent on powerful OGCD abilities, where the idea was to make WHM's flow a trade off of reducing their cast time (but not the gcd, to enable weaving) for said abilities. The TL;DR was this

Casting Cure spells generated a Lily. Casting Stone spells would generate Lilies but at a slower rate (essentially creating stacks that where consumed to generate lilies every 3 times Stone spells where cast)

Aero ticks would generate a Lily when they crit (with an internal cooldown) Regen had an X% chance and Medica II had a Y% chance to generate lilys when they successfully healed. (with its own internal cooldown as well)

Lilies stacked up to 3 times, each stack reducing the cast time of their Cure/Medica/Stone/Holy spells by .25 seconds. Capping at -1 second. GCD is not effected by this, thus meaning every spells had Malefic cast time.

Finally I had 3 OGCDs that consumed the Lillies.
Salvation: Single Target Heal + Regen refresh.
Plenury Indulgence: Reworked into the AoE version of this "Salvation" effect.
Tornado: DPS dump + Aero refresh on the target.

And ofc, a cooldown that instantly filled the lily guage, iirc i made it 45 seconds.

The whole idea was that as you kept actively using your gcds you would gain stacks that would essentially give you the weaving space needed to use your OGCds and then you would spend the lilies to either heal as needed or to refresh your Aero dot. Granted I'm aware that in this model most WHM's would likely dump the lilies on Tornado 90% of the time in this model, but that's just a matter of tuning, even if it means removing the damage on Tornado and renaming it to something less badass.