Both are significant for the story yet both suffer from under and overtuning:

- CT is just a DPS fest, where some bosses barely are able to do anything (Glasya, my beloved) due to the high damage output of the raid, unless they are forced via one-shot mechanics (like Phlegethon's Ancient Flare and Amon's Curtain Call).
They could do well to improve the bosses (HP and damage wise) and have them punish the raid more for ignoring mechanics. Not to mention seeing some of them the first time when bosses live actually long enough, making them more interesting again.

The Crystal Tower, in its current state, gives first-timers a false impression of how alliances work.

- The Binding Coils has a lot to unpack, lorewise, but nearly everyone does them on a high level to brute-force the content, if they even bother. Or worse, didn't knew it existed in the first place because of how obscure it is to find the quest starting it all.
And even then the one or other fight won't work due to certain mechanics (Hello there, Nael), which means you have to rely on others to help you. And the interest in that is nonexistant.

A few fights need to be adjusted and remade (like the lift and platform sections), but some of the encounters are really interesting and should be kept, just more adjusted to the current item level, streamlining them like they did on HW onwards.

Giving out new rewards in tandem with the rework definitely could help getting people back to the coils. There are great fights, lots of story and a pretty satisfying ending, which players should do before they tackle HW content, since clearing it also changes the dialogue of some NPC's.

And the cutscene. Come on, that alone is worth it going through that all.