The new metal detector is a great way to make gralats on zone, currently being its pretty hard to earn them. But it still needs a few things added to it to make it better and easier to use.
Sound:
There should be a sound that happens when you press the metal detector button on your hot keys. And maybe even a different sound for when you use it over a piece of robot.
Pop-ups
Everytime you pick up a piece there should be a pop up at the bottom of your screen saying: 'you have picked up some/a _____'. It would make it a lot easier to tell if you have picked it up, because you have to be 100% on top of it to pick it up.