While I enjoyed HW, I don't think it would work with the current playerbase. In particular, the concept of sacrificing dps to mitigate more or heal more probably wouldn't go down very well. Setting aside the fact that Stormblood was objectively DRK's weakest expansion (which was reflected in player numbers as well), it really highlighted how unnecessarily long a lot of the oGCD animation locks were by making everything a mandatory double weave with DA. That expansion was also the turning point where players realized that they weren't going to put up with gross inequities in job design, like a 180s recast Shadow Wall that offered none of the additional benefits of the 120s Vengeance or the 40% DR Sentinel. Please don't get me started on how bad that expansion was for DRK.

I think DRK needs to be oGCD heavy at baseline, because that's the one recurring design point. You can make the periods between burst windows more interesting by offering more variety in GCDs, or perhaps even experimenting with actions that speed up your GCD like Blood Weapon used to. There may be some value in looking at the size of our resource pools relative to action costs. I think that adds an element of strategy to fights, where you potentially could consider skipping a smaller burst window to pool up for a bigger one under buffs (i.e. Triple Enshroud under Potion). But that works better with a job that is almost entirely resource gated rather than time gated.