They are all guilty in their own way. It's YOUR personal choice as to who deserves what punishment.Personally, letting Abigail die at the hands of a mob is MORE evil that letting her live. Especially when you believe her later statements of being a changed person.And as for all the dead bodies around the village you notice after slaying the beast:The Reverend went against your suggestions and let the people gather outside. This was a seriously BAD idea with the Beast and its demon doggies around, especially at NIGHT!He knew it, thus their blood is on HIS hands, not Geralt's.