I made this observation in another thread, but it seems like tanks can be placed into two categories in terms of rotational mechanics: knights, and berserkers. PLD, and GNB are knights which focus on using multiple combos, and WAR, and DRK are berserkers which focus on spamming heavy hitting attacks. So I feel like a way to get the warrior stink off DRK while maintaining berserker-like gameplay would be to give it a second combo to build towards like it's a knight -- it is a dark knight after all. Perhaps DRK's gcd rotation could resemble a knight's, and its ogcd rotation could resemble a berserkers.

Another thing that I feel needs to happen to make DRK feel a little more special -- and really lean into the themes of self-sacrifice is to figure out how to allow it to safely spend its own HP on attacks instead of MP in pve duties.