I'm probably late to the game here, but...
Stalkers were my fave back on Live (and my current-sort-of-Main). Like how Doms had a set pattern of play ("Control, then attack while they're helpless"), Stalkers did too, "go invisible, drop the biggest target, then punch away at anyone else (and Placate might save your skin)."
The crits from Hide are nothing to sneeze at, and that ATO just gives you more, so they're wonderful.
These days of course, they play a bit differently, so they're sort of strange sideways Scrappers. I tend to open up with an AoE (if I have one) to crit it across everyone I can at first, and THEN slam the biggest target with AS... to possibly go back into Hide for another AoE crit. (Then again, my Main is an AoE king amongst Stalkers because he uses so many Combat TP powers to open things up; it's a whole thing.)