1) Mara Sov is currently MIA. I would think we'll see more of her when the next Fallen-focused expansion comes around, seeing as the Awoken and Eliksni seem to be closest of any two races. 2) The Temple itself likely is unsafe, seeing as Tyra Karn is currently residing at the Farm in the EDZ. As to Saladin...it's possible he didn't make it out. 3) SIVA (a) is currently inert/destroyed by our hands, buried under the wreckage of the bunker. However, there are other samples, such as SIVA (b) which is somewhere near the Exodus Black. 4) The original areas are, at the present time, non-significant to the Red War arc. Presumably, they've been occupied, but don't hold any real importance to the Cabal. 4a) The Dreadnought is likely considered too much of a hotzone, and is simply being ignored, for fear of the Taken 5) The Stranger is still a mystery. We may find out more, if there's a Vex-focused Expansion

Heard a rumor that the VA had to do 2 versions of the Awoken Queen, one was the version we got and the other was more like a space pirate queen and that she said they "weren't finished" with the space pirate version and that they are gonna bring her back in D2 with that role (personally I think she's still alive since we never find concrete proof, like a body, that she died)