With weakness changed to no longer affect VIT, it now pretty much works as an outgoing damage/healing down debuff. Why not just change it to exactly that instead of doing it via attribute debuffing so that tanks can scale damage off of VIT? VIT-based DPS for tanks with the current weakness/brink of death would be pretty broken as tanks would just shrug it off and do full/near-full damage with VIT unaffected.

As for the HP scaling vs. DPS output issue if tanks go back to scaling DPS off of VIT? Simple, change the amount of HP per point of VIT to set the desired balance in that area. Sure, that might effect other classes, but as I understood from the old PIE to MP increase ratios from before, the scaling was different per class (or at least role), so why couldn't VIT -> HP also scale differently per class/role?