As stated above (And I've stated it myself numerous times), a big part of the issue here is that I don't think Yoshida has any 'career healers' within his class design team, as a result they are falling foul of issues that have been seen elsewhere in other mmos that eventually needed to be addressed to move forward with raid content.

On the content side, I think SE need to be more unforgiving and cutthroat with their design. Whilst O4S isn't quite as extreme as A12S was, it still has significant amounts of breathing space where very little to nothing is happening that isn't entirely avoidable, whereas the big damage that does come at you falls perhaps too neatly in line with both tank and healer cooldowns. The double thunders during delta can both be outright ignored by any comp, whereas Almagest lines up perfectly with Shroud/Thinair for the majority of the encounter.

Hit's don't need to be bigger, they need to be sustained over longer periods. Aoes need to be more frequent to run healers out of oGCDs and cooldowns. Damage needs to go out across more than just one target. They've done these things in various encounters already, it's just a case of them having the bottle to throw it all at us at once in an encounter that isn't quickly going to be trivialised by the gear we obtain. T13's first phase breaths+stomp at min ilvl is a fantastic example of this and they are very intense to heal though. SuperSavage should be much easier to tune for SE since they will just aim it at ilvl 340 and that's that. It'll be a stern challenge (hopefully!) until the next major content patch which will just render it obsolete anyway.