So I just taught another one of my friends to play and from a brief description of the fluff he was interested in trying out Sonnia.
We played starter box v. starter box, so I had:
Seamus
Sybelle
Belle x3
8ss
And he had:
Sonnia
Samael
Witchling x3
8ss
The only defining feature of the terrain was that there were two "Mysterious Effigies".
We had Shared Turf War for a strategy. As for schemes, I took Bodyguard Seamus, he took Kill Protegée on Sybelle, and we both took Breakthrough.
After two turns of luring shenanigans and Seamus popping two witchlings, Samael was dead, Sybelle was badly wounded and I had summoned a fresh Belle.
Sonnia then managed to burn out Sybelle for two VP- and a new Witchling! I then summoned a second Belle (too bad I only have three figs for them >_> ) and ran it over to my deployment zone. I quickly sent two of my Belles (one of which was definitely Witchling bait at one wound) over to his deployment zone, leaving one to guard Seamus, who was standing near an effigy. I then used his Flintlock and my last Belle to put Sonnia out of her misery.
Final score was my victory, 9-6.
All in all the Sonnia player did very well for his first game, I think she might be one of the better 'teaching' masters. We both felt it would have been closer had he known that soulstones did nothing for you at the end of the game- he had three left when the game ended.