My personal theory is that the Sires are human test subjects who have had prolongued exposer to Immulsion. Sort've like Rustlung, but to the extreme. I also believe that Ruth was one of the Sires, as extra long nails and no hair seem to fit a basic Sire design. I'm assuming that they were kept in New Hope for containment while the scientists attempted to cure them.
As for the Queen, I suppose it is possible that she is a humoniod Locust, but the theory doesn't really fit in with the idea of the Humans invading the planet Sera (which I personally believe in). I also think it's a possibility that the 'queen' is merely a host for the true Locust Queen, and is simply being controlled (I hesitate to use the word possessed) and spoken through.
In regards to Adam Fenix, I believe that he was taken captive by the Locust so that they could gather information about the Human race. The queen most likely heard about Adam's profile of being a respected scientist (possibly from Niles and his crew, as they may well have strolled into the Locust stronghold without realising), and launched a snatch and grab for him. It's possible that the queen used the collective knowledge of various high profile humans to better strategise. That or she hoped that they would be able to cure the Immulsion-exposer illnesses that was causing their civil war.
What about Lost Odyssey? The funeral for Kaim's daughter is pretty damn emotionally heavy. And then there's the 100 Years of Dreams, too. One of those were absolutely heart-breaking!
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