Lust and battle res are sometimes the things you fill last if you didn’t get them from DPS, so it’s a nice boon for a healer to have them even if they’re not that interesting by themselves and can be filled by other people.
Holy Priests in Shadowlands seemed to prove you don’t need either of those things to make it to the top though. They also have no DR external. It seems like every spec is just minor tuning changes away from being bottom or top if a holy priest can temporarily be the top healer in a M+ environment.
There are other useful utility at least in 5 mans to consider as well. Maybe people wouldn’t consider them major, but things like an interrupt and AoE stun can literally be the difference between a wipe or not in M+. IE: if someone doesn’t CC the imp groups in Court of Stars at higher levels (especially on Fort weeks) your group just got blown up. Quite of few things need to be interrupted in many dungeons.
AoE stuns are very useful. Monk has one. Leg Sweep is better than Tail Swipe or Incapacitating Roar (the closest equivalents from Evoker/Druid which I just mention since those are the top 2 healing specs atm). Evoker also has Terror of the Skies if talented, though that’s a 2m cd.
Monks having a melee interrupt is strong 5 man utility. Resto druids do not even spec into their interrupt most of the time because their tree just makes it hard to give other things up. Evoker interrupt is on a longer CD.
Ring of Peace can be used as a psuedo-interrupt against certain mobs and can be used in some useful ways to keep enraged mobs or spiteful etc away. I do think it would make sense to add an enrage dispel to this as well since it would fit thematically and enrage dispel is useful occasionally in M+.
Paralyze is more versatile than entangling roots and probably about the same as sleep walk (though most evokers don’t spec into sleep walk anyway where paralyze I think is more commonly taken). Paralyze can be used to stop some casts as well.
Song of Chi-Ji is not taken probably because of the competition with so many other talents you’d want, but I think it would have occasional usefulness if you could take it. Perhaps they should try making it a baseline MW ability?
I would have loved to see Legacy of the Emperor return as a Monk group buff, but I think the 5% physical damage debuff is probably why they weren’t given this back. Or the short range aura buffs in the general tree maybe. The group leech buff would have been huge but it was nerfed in beta to be a group healing received buff.
Tiger’s Lust isn’t huge, but having a single target speed buff is nice. Monk, Priest and Pally have this I think. Blessing of Freedom and Tiger’s Lust can also be used as a dispel for certain debuffs that happen to both deal damage and slow. In Shadowmoon as an example, there’s a disease from the bats that slows and damages people I believe (or it might be poison I forget). This kind of utility would have been bigger in expansions where tanks had to kite certain things.
When it comes to contributing damage in 5 mans, I think the ease of doing that is an important factor because you want to minimize GCDs spent on damage while still contributing. Disc/FWer are a bit different since there’s overlap between the DPS and healing. Druids can just dot things and do mildly useful damage (not breaking records though). Evokers damage is very bursty and they can fill with damage dealing living flames while fishing for essence burst procs. I think fistweaving can contribute quite a bit of damage, but it’s more GCD consuming, has the faeline + melee range limitations and I feel like it makes people feel a bit less in control of the healing aspect when there’s an emergency since there’s a significant amount of healing coming from “semi-smart” effects.
TLDR: lust and bres are important, especially when forming a 5 man, though holy priests made it to the top at one time without them + discussing various kinds of other utility that are useful in 5 mans