I'm gonna assume you're one of the 10,000 people who get to learn about the Seven Heavenly Virtues today. (Well, realistically it's lower than that, but—whatever.)
No I'm well aware of them. One of the topics I like to read in my spare time is theology because I'm a big nerd.
I figured I'd write out a fuller summary of my reasoning since if it's coming across like 'oh, they've probably not heard of the Seven Virtues/Vices' I must have been communicating my intentions poorly. Also, to be extra clear, this isn't intended as a rebuttal of any kind it's just more of an 'oh damn, didn't make myself clear there either, better write out a short summary of the sources for theological development I was drawing on to comprise my logic but didn't actually mention.
So as for my logic, along with being aware of the Seven Virtues/Vices model, I'm also aware of how the Catholic tradition that developed the standardised model you're talking about with Wrath vs Patience is not only not being culturally adjusted for the drift of time, culture or language (it's in Latin); but also it is also has its roots in Jewish traditions which were then passed through the sieve of non-Christian Greek and Roman philosophies by the time we hit Paul's virtues and then later Prudentius' list of Seven Virtues and Vices in the form of poetry. And since I don't feel like it'd be productive for textual analysis to try and get into the head of a Roman Christian in the 5th? century to try and justify the Wrath vs Patience thing in the Latin of the time, I think, lacking the aforementioned contextualisation, it seems fitting to set that aside that dichotomy as inappropriate for this instead.
Thus, we're left with a few other options when considering the theoretical instance of a dark magical girl of Wrath which we can speculate about since we know it's a canonical possibility. And given the reasonably consistent and long-standanding references to The Wisdom of Solomon/Book of Wisdom in development of historical Catholic conceptualisations of sacred virtues, I picked up Righteousness for basically three core reasons:
a) It is an obvious counterpart where the aforementioned sin can still be present in the person but nonetheless be a force for good, texually speaking and fitting with what we've seen from ALV's cosmology (in my opinion, at least)
b) Mundane real life reasons (righteous rage is a common phrase in contemporary english-speaking cultures after all and the concept is hardly unique to them)
c) And finally the fact that Righteousness is also repeatedly referenced with regards to the Wisdom of Solomon by various writers who were part of the development of historical Catholic conceptualisations of sacred virtues.
Thanks for reading to the end, if you have. This
is the short version, I promise.
Edit: SNIPED AND JOSSED BY SHADELL LMAO.
I do still think what I suggested was worthwhile though becuase I think it'd make an interesting story with fun historical theological themes to draw on (just evidently not one entirely fitting with ALV and Shadell's vision for it).