Being balanced only for harder difficulty sounds like a bad concept.
I'm not saying it doesn't need tuning, only that 'balance' is relative.
I'm sure Warlord is even more OP on Explorer than Classic, but it can't be tuned to have the same relative utility on all difficulties simultaneously.
Heck, if nerfs come in on some of the other overtuned sources of power (such as Flesh Sacrifice) Warlord and Rage will be less potent in the current environment even.
These abilities only have tremendous power (without drawbacks) when 1 team overwhelms the board.
