Stalkers are best at killing bosses, and if they ghost paper missions, bosses are about a quarter or more of all their kills. Bosses are more likely to drop salvage than others, so if anything stalkers will be getting more efficient salvage per mob than others.
Hide is fundamental to a stalker's power. Stalker's inherent is Assassination, which I'm sure you know, allows them to achieve critical attacks 100% of the time with most moves if they attack with the power Hide activated, if they are not otherwise affected or affecting in the last 10 seconds. A stalker can also use Assassin's Strikes from Hidden, a state which can only be achieved with the power Hide or for a few seconds after using the power Placate, which has quite a long recharged compared to the 10 seconds you would otherwise have to wait.
Just because invisibility may be achieved, even though it won't and it will just be hightened stealth, it is not nearly the same as Hide, as an invisible stalker is not necessarily Hidden. If all stealth was the same as Hide, rest assured I'd get the Cocnealment pool on pretty much every character.
The only difference Stealth IOs make for stalkers is that they would be even harder to see, though I do not know the numbers for the IOs, but in conjunction with Stealth and Hide, you'd be pretty hard to spot even with perception. Hooray for Stealth IOs 
@Rooks
"You should come inside the box... Then you'll know what I mean."
According to a guy on the us forum (can't remember where i read it but pah) who supposedly tested it stalkers can now reach the stealth cap with hide+stealth+stealth IO. No more need for invisibility in pvp hurray!
YAY! buff them even more so that it fecks pvp even more!
joy! >.>
As a stalker I feel like stalkers are at a fundamental disadvantage when it comes to the IO sytem. Were stealth chars, we only engage what we have to or whats fun to do. Ghosting missions is one of the best parts of being a stalker, completing a mission in 30seconds cos we can just run to the end and do it is great. But when we have to kill stuff to get recipies and parts, whats this mean for stalkers? Anyone else forsee a slight problem with this system for this archetype? We gonna have to start clearing out all our missions just to ensure we get all the salvage? Or are we simply going to be spending insane amounts on the black market in order to buy things? Or just be gimped cos were the class that unless teamed, or its the mish, rarely take on the whole map's spawn and therefore dont get the all the invention origin enhancements?
Also with all the new stealth IO's coming out, will hide become a power only usefull for PvE? Or will the perception race take a new leap forward?
Anyone else feel that stalkers are put at a disadvantage with this system?