I would love for this to be implemented.
Part of this is because I would seriously love to be permanently able to see the both of them. It would help a lot. The other thing is that it can occasionally be hard to see what exactly the terrain is doing, and the way that f4 metalmap highlights terrain aspects on certain maps (2 mountains battlefield, DSD, greenfields, as brief examples) it's actually very useful. So if the two could be able to be switched on at the same time, I'd love that.
EDIT: But then I have to ask - is this game-specific or is this engine? Because honestly I'm unsure.
LOS + Metal view