Perhaps a Simple DRK Solution

[Chronons]

It honestly sounds like you just want DRK to play like a DPS class man xD

What leads you to believe this? Having BfB would encourage DRK to stay in Grit while MT. While in Grit+Darkside+BfB you are (+5% in +5% out damage) while in Darkside alone you are (+0% in +15% out damage). The difference is that BfB has the benefit of not costing any MP and not costing a GCD to revert back to the tanking stance. Further, you would not ever want to use BfB outside of Grit while MT as you would have +25% damage incoming. DRKs niche among the tanks is its ability to do the most damage while in its tanking stance, this change only improves upon that.