I do like this idea,
However, not for the sneaking part of it.
I know for a fact, if im ever being attacked by a group of people, or hell if im defending a place, there is a limit on how far you can see.
Now- Defending a place with this would be made a whole lot easier, you could just set it onto spray, wait for somone to go near the door... (You may not be able to seee them, maybe have a sneaker outside the base, tell you when they are outside door, then you spay)
This would damage them, and cvhances are they would step back, possibly going away.
Also, i believe rockets should have a "Aim to floor" Function, taking up all your AP at the time, you should be able to aim at the floor of an area, causing a DOA, and if you are watching a place, you can fire it just thrugh the door, or past cover, one hex past the cover, and decimate all the injured behind this aforementioned cover.