Let's take this discussion in another direction. Let's talk about class balance in a hypothetical Classic+, what do you think it should look like? Forget content, that's wishful thinking and we can't really affect that anyways, but I think Blizzard takes community fededback into consideration when it comes to class balance.
In my personal opinion, there shouldn't be a heavy "hybrid tax", but only to a small degree - and purely in terms of DPS.
For example, I posted in the previous thread what I think an ideal DPS chart would look like:
>Rogues
Because they're the only pure melee DPS class and are a "selfish" class.
>Hunters, Mages and Warlocks
Because they're pure DPS classes, but ranged and bring more utility to the raid.
>Enh & Ele Shamans, Fury Warriors, Shadow Priests,
Because they're two-way Hybrid classes
>Feral Druids, Ret Paladins
Because they're three-way Hybrid classes
>Boomkins
Because they're a three-way Hybrid class and a ranged DPS spec.
Conversely, the further down the DPS chart you are, the more utility you should bring - while DPS'ing.
And then Healers and Tanks.
In terms of Tanks, I personally think each Tank spec should have a niche. The way I imagine it is as such.
>Tank Warriors
The best boss tanks through having the best damage mitigation
>Tank Druids
The best off-tanks through more taunting options, while providing group utility.
>Tank Paladins
What do you guys think their niche should be that is a valid role in raids? "AoE tank" is an easy answer but I think that relegates them to non-raiding tanking.
So perhaps they should have worse damage mitigation than Warriors and potentially Druids, but better single target & AoE threat generation, that way, by choosing to go with a Paladin tank above a Warrior or Druid, you would increase the potential DPS of your raid by virtue of people having to think less about overaggroing?
Healers: Either Priests & Shamans are straight up better healers than Druids and Paladins - or different niches.