Sanctuary seems to be grasping for a theme.
Rapidly changing arcs and characters are not a good sign and reminds me of the fall of Atlantis(the SG series, not the city). Even more troubling is the sudden influx of CGI monsters, like the are trying to be Primeval the BBC series.
When it started, I was expecting (from the first episode) something akin to "Beauty & the Beast" as far as the Sanctuary itself was concerned, mixed in with a little of whatever the Army called its base in that season of Buffy.