yeah this is what id do.
you dont really need to buff the tanks just adjust the pain points.
like for instance you nerf the healing cap but you also nerf the dmg cap, nerfing/reworking the ‘tank busters’.
you have to nerf healing before you do this otherwise the tank would never die.
currently things have to exist as they do because of the sustain. this then makes burst dmg and anti healing effects infinitely more powerful then they would of been otherwise.
if you make it harder for supports to keep everyone alive, then the tank no longer gets hit with every CD because its no longer necessary. and they (the tank) can more easily kill things and get value without needing to be hard pocketed themselves
the overall tank experience improves as a result (as well as everyone else’s)