I kind of wonder with the sudden rise of the Sith, what the Empire's stance is concerning them. I know that Miranda has a secret training dealy with Salem in the deep dark background, but are all of these Sith in league with him, or do we know? If not, should the Empire be taking steps to deal with a potential threat?
It'd probably depend (at least partially) on what the Treaty says about Force users. Presumably, there's some sort of clause or stipulation about the Jedi, since they're all safely nestled in neutral space and all that. If it's some specific clause that refers only to the Jedi, then the Empire presumably has free reign to do whatever it wants about the Sith/etc. If it's more of a "freedom of religious expression" type deal, then the Empire would presumably have to (at least seem to) handle the situation with gentler hands.
Not all of the Sith are in league with Salem, and he will certainly be suggesting - in discussions like the one taking place in Chalice and Altar - that the Empire should be very vigilant of Force Users in their borders.
I kinda look at it like this, if you aren't one of the Imperial Knights you're out of bounds. In the case of the Jedi, just stay out of Imperial space. Unless you're a specific Jedi that needs capturing All others are considered to be a threat and dealt with accordingly as Vega set a bad precedent