What you’re asking for is them to balance ‘optimal’ rather than ‘viable.’ Which is literally impossible so long as the specs play differently. As I said above, it sounds like there is only one solution for you to be happy. Make all the specs play identically, with identical utility, and identical defensives.
So long as specs have varied damage patterns, there will always be imbalance at the level of ‘optimal.’ Hence why it’s more important to shoot for ‘viable’ when balancing.
As an example… if spec A does more damage but requires ramp time, and spec B deals all of its damage during the initial burst… Which spec does the most damage will be entirely dictated by fight length. The longer the fight, the more spec A will be called ‘OP.’ The shorter the fight, the more spec B will be called ‘OP.’
And that’s just looking at a simple ramp vs burst damage pattern. That isn’t bringing in ST vs AoE vs Cleave vs Funnel… or CD timing… or class synergy… or talent choices…
In order to reach optimal balance as you require, all of those would have to be normalized across the board. No thanks… I’ll take what we currently have, which is everyone is viable into the low 20’s, but if you wanna really push… yeah you’ll have to pick a meta spec.