Let's not make Charmyna into the Dark Destroyer here. Charmyna's a very good player and an even better spellbook designer (better than I at both) but not the grand champion who can never be defeated.
And more to the point, I don't know if Charmyna has made any statements suggesting that Wizard's Tower needs to be nerfed. Lets not put words in Charmyna's mouth.
And even more to the point, I do think that a lot of the negative reaction to Wizard's Tower is because it's flashy. It gets a lot of attention playing attack spells that are tactically really strong, but cost a lot of manna somewhat inefficiently. But when you lose to Wizard's Tower you know it: your stuff got slammed, dazed, pushed, set on fire, and crushed to death.
Battleforge, which I have never heard anyone call to be nerfed, is very nearly as powerful. It's just much quieter, and far more long term strategic. You have to be paying pretty close attention to know that a Battleforge killed you.