Since PA is recently looking at fixing inequality in PvE, I'd like to point out huge gap in performance between classes in Black Shrine.
I have no data, as it's not accessible, so all we can do is look at in game ranks. I've checked Sangoon C8, as it seems to be one of the more popular choices.

There are classes that have huge amount of players beating it under 5 min, but there are also classes where people struggle and barely anyone is attempting anymore.
I'm deliberately not naming any classses, as anyone can check it and I'm writing this not to attack well performing classes, but rather to ask PA for action on behalf of the weaker underperforming classes.

Now the question: why some classes are underperforming? Assuming it's not strictly popularity issue*. I can only guess, and I bet PA knows more, but from my point of view I see following issues:

- Gaps in protected movement. Some classes have spammable PvE iFrame**. Sure, the stamina is issue, but it's making it much easier to avoid some boss attacks.

- Continous damage. Some classes have readily available consistent damage that shreds boss HP when it's not in invincible state (which some bosses do a lot). Other classes have burst damage on long cooldowns.

- Self heal. This one is self explanatory. There are classes that can heal themselves more efficiently.

Fixing first issue would be, IMO, rather easy. Just add spammable PvE iFrame to all classes. Before anyone is outraged - I mean PvE iFrame, not regular iFrame. As for other issues I have no answer, but again... I'm just mediocre player.
I know one of the answers is to use alt, but that's not really a solution if we're considering calamity 8+ bosses, where actual gear is needed and tuvala shai alt is no longer viable.

*(only 2-3 people playing certain classes in EU met gear requirements? maybe, but I truly doubt)
** this is what I mean by PvE iFrame:

On classes without it, you have to unlock evasion and use the default roll. Pretty lame. Would way rather have a built in one or add PVE iframe to more skills.