..well, true enough solo weapon-based heroes might be a problem, however Visage+Coating should absorb good chunk of that damage (unless they have 9 resources and Sever Ties + LLN in hand to destroy it), however:

a) i don't see that many solo heroes in QM/Tournaments
b) you have Scourge and 4xShadow Knight, so you will eventually win through the board