I was asked to raid heal last night on my druid and I’ve not done that for a very, very long time. I think the last time I raid healed a boss kill was in Sunwell, at least on my druid.
I’ve done M+ healing but that’s a different situation as you’re running as many DPS traits as you can get away with.
Being so out of touch with raid healing I looked at the guide, chose talents I thought I could handle, chose the 2m tranquility talent as that was requested for better healing CD coverage and pressed the Find BiB button.
What I discovered seemed odd so I had a look at the boss script.
The optimiser has a real hard on for Vampiric Speed.
I don’t know if healing someone who’s damaged it triggers it or not but it matters not for this inquiry.
So what should I choose for a fight against just one boss?
I was thrown in the deep end for Mythic Abyssal Commander Sivara and there is nothing dying there except my team mates. 
Looking at the results of BiS, with 415 ilvl azerite pieces and just heroic raid gear, it chooses three Vampiric Speed pieces, clicking on the traits shows 1.22% - 1.29% above the other option on that ring.
I’m not sure if that’s a ~1.25% total healing increase or something just relative to the traits on that piece of gear, whatever the case it’s not something I can get on a fight against just one boss.
If this was for DPS I’d have a better idea of how the other options stack up in a situation different from the script, but for healing I’ve got no idea, you could say I’m clueless!
The mythic version of the fight would probably make for a pretty good boss script, although executing like a script does would be difficult.
I think it would be handy to have an option for healing between the M+ boss fight and the Vectis script but understand that’s a lot of extra info to get across to end users, it’s also a lot of extra simulations.
Thoughts please @Swol. 
I suspect you’ve got a much better idea of how things might change, you’ve probably got a few ways I could suck less at healing too!