I definitely think option B is the way to go, even if they need a bit of time to implement it. It'll fix all the issues and allow jobs to not be too similar (i.e. not all of them need to have % damage buffs). DNCs won't have to use a direct crit attack under Devilment, DRGs won't feel weird having to use Life Surge during Litany, MCHs will be more desirable as DNC partners, and so on.
I actually propose the same change in my DRG feedback post (
https://forum.square-enix.com/ffxiv/...-for-Endwalker). To be honest, this wouldn't be a drastic change on the jobs affected because it's something that's only going to happen for 15-20s every 2 minutes, and the damage buff should be similar to that of any other normal buffs like Embolden or Trick Attack. The only "issue" could be Devilment with a WAR, but I'm sure that if that got out of hand, they could reduce the effect Devilment has on WARs, yet the more likely scenario is simply that a WAR will never get more benefit than a DPS, even with this change.
As numbers can always be adjusted if needed, this is a necessary change. It's not about parsing, it's about the fact that there's specific jobs that feel too weird when they have (direct) crit chance buffs. Why should WAR be the only tank negatively affected by buffs? Why should DRGs or DNCs have automatic (direct) crit attacks that must be used during such buffs (and so be negatively affected too)? This change preserves the identity of the jobs while allowing them to benefit from these buffs. It's like having an extra Embolden, Trick Attack or Technical Finish for a very limited and specific number of attacks, so balance shouldn't pose a problem.