TBN in concept is great. A shield where you take 0 damage while it is active is good in any content. The problem is that it's either viable in single targets or ineffective in dungeon pulls. It's design is antiquated as well. It's the only tank cd, exception of LD, that actively punishes you for using it wrong while the other tank cd equivalents can be used almost anytime.
I think TBN should be on 2 charges. That way its more easily accessible. Ultimately TBN is the sole reason why DRK no longer has self sustain. If you take 0 damage then why would you need to heal?
Outside of that I think the change to SAD was unwarranted with the new aoe cursor limit option they added. It just feels more restrictive now as I have to physically move to the enemies to place an aoe.
Like I said, the bare minimum I expect to read in the patch notes this Tuesday is:
-TBN duration increased to 8 seconds