[X] Plan Bii
Now, as far as canonizing the omake goes, I can see Emma going one of two ways, which also would determine how experienced she has gotten.
Option one: she went the canon route and cut Taylor loose, despite having gained her own power. She would have fallen into a rut with Sophia and not really acomplished anything in the last year and a half, gaining ~15xp from the downtime trickle. She probably would have taken part in Sophia's brutality and gotten forced into the wards along side her. Boring.
Option two: she keeps her best friend beside her, integrating Sophia into the group and becoming a trio. Taylor and Sophia initially have some friction due to Taylor's (still) bubbly personality, but Taylor manages to shift the dynamic enough that the train gets off the rails and goes in an interesting new direction! Emma and group work on something new and interesting; maybe actually cleaning up the streets, perhaps using B-A-B I to tear apart the gangs? maybe they figure out the permutations of Emma's powers and how they improve and strengthen over time? Possibly even managing to accidentally sorcery? Regardless, they actually do something Heroic (in Exalted terms) and Emma really has been sweeping up the XP, right along side Taylor and SS, who manage at least Heroic Mortal tier.
The only thing I don't get is making Emma an Earth caste, as I feel she is far more fitting as Fire.