People using a review metric are trying to quantify a subjective experience which doesn't really mean anything until they provide context (like you pointed out). People love numbers/grades though so, that's why professional critics use them and why people will use them casually.
As far as Faora goes, speaking for myself, I said she's a
scene stealer meaning nearly every scene she's in (a lot of them action scenes) she's directly involved in some form of badassery that frankly, I would've expected to be given to Zod. Also, Faora uses a super power that's portrayed in unique way in the movie: super speed. Her almost seeming to teleport flurry punch was visually impressive, distinct, and got a HUGE reaction from the audience in the theatre I was in. Even my girlfriend was all, "This chick is a badass! It's like a video game!". Combined with going toe-to-toe with superman, stone-dogging the US Special Forces, this ominous indomitable presence was portrayed perfectly by
Antje Traue (which was genius casting). Faora personified the unympathetic resolve of the Kryptonian Resistance in a way that was both different than Zod (who was shown to have his own morality and ethos), and in stark contrast to Superman and what he represents.