First of all, Sword Oath is the most potent DPS stance adding roughly 11~15% DPS compared to base non-DPS-stance. While it would be nice if it boosted potency of attacks which would help with aggro a bit. I do not see it happening though.

Shield Bash moving to off GCD means it loses 1 second in duration and gains a 20~ second CD so it is in line with the other stuns. It would gain a form of advantage but it loses the stun lock advantage. I think it is nice in its niche form currently.

As for DRK, Blood for Blood would make healers' lives a nightmare. The amount of bad DRK tanks out there is bad enough, adding more reason to make the bad tanks even worse is not the smart idea.

Keen Flurry would be a nice addition but it does not justify changing MRD to LNC cross class. Same with Invigorate. IMO DRK needs their own versions of those skills. Dark Dance should add more than the measly 30% parry rate. And if DRK MUST get a TP replenishment, they should have their own version.