It seems that I will have to stand up in defence of Virtue.
First of all, she isn't meant to be SC, and most and if not all critics directed at her look like people expect her to take whole armies by herself.
Here is some pros that most seem to forget; she costs only 50 points for which you get a flier with great starting dominion (4). She is also excellent for high scales strategy - example:
Machaka with Virtue - +3 Order, Production and Growth and +2 Heat, 7 dominion strength, castle and level 5 in air is quite good and gives Machaka another magic path they are weak in (and allows easy Flaming Arrows + Wind Guide strategy) while allowing you to crank troops and mages at insane rate. Later on you will be able to amass large numbers of troops that she can protect with mist warriors spell.
Early Awe + Mistform CAN be used to beat independents; later Storm + Wrathful Skies is much better for her. Like Allfather she is a flier and can attack key provinces fast, but unlike Allfather she comes with lightning immunity and has no need to cast protections or wear items to protect herself from her own spell. With boots of speed she can cast both spells at the turn one.
Due to her flying/air skills, she can be used to support advancing armies and cast mass protective spells (like mist warriors) fast and without terrain restrains.
Of course, she has weaknesses, but undead are hardly one of them since she comes equipped with Flambeau that is designed to take them out. Of course masses of them will kill her but so will VQ as well. Key is to keep her mobile and out of the melee while doing carnage from afar. For the price she has lots of uses but I wouldn't mind her getting buffed up to the combat level of Moloch.
Couldn't help myself, had to help a lady.
