Once upon a time, I did a little "What if DNC was a healer?" Theorycraft back in Shadowbringers that looked kinda like this...

Damage potencies dropped, naturally, but the toolkit largely stayed the same in terms of actions, though some actions had their effects changed. Standard Step currently gives you one two-step button combo to press in order to gain the maximum damage and buff. This stayed, but you'd have the option between that 2-step combo and a second using the remaining two steps, and you'd pick which one to use each Standard Step usage. The second combo would grant the party a 15 second Bloodbath-like effect that healed them when they used a spell or weaponskill. Since the Standard Step buff lasts 1 minute, you could use the recovery step instead every other Standard Step in theory. Technical Step would grant this effect on top of its current effect, making it easier for you to go into an offensive burst phase. These changes would also have made Tillana's effect more clearly valuable, whereas now, it feels very redundant. Meanwhile, Improvisation changed to a potent burst heal you could only use while using Standard Step or Technical Step before you finish the dance, that way if you were caught in need of healing while you were dancing, you had a way to heal the party. With Improvised Finish being added, it could be an additional OGCD burst heal you got after triggering Improvisation during one of your dances and could be used both in and out of dances.

Curing Waltz stayed the same but moved to the GCD in addition to Divine Waltz which was half the potency but a much larger AoE. Fan Dance III, however, would upgrade them both to Curing Waltz II and Divine Waltz II for 1 use, in which their potency stayed the same, but they became OGCD. Flourish also granted this proc. Then you'd have Astral Waltz as your raise and Healing Waltz as your Esuna. Astral Waltz was instant cast by nature, but debuffed yourself for 1 minute making future casts of Astral Waltz have a cast time of 8 seconds, effectively building Swiftcast into it.

Saber Dance was removed as an Esprit spender and just made a GCD cooldown. Meanwhile Shield Samba had its cooldown reduced to 30 seconds and used for Esprit along with Drain Samba that gave the party that Bloodbath-like effect from Standard Step and Technical Step, and Chocobo Samba which gave everyone combat sprint (I know Expedient was a meme prior to EW's release, but I always liked the idea of movement speed buffs). So your Esprit was basically a buff gauge.