I think people love or hate them, but you could play with o-rings as well.
O-rings for Cherry MX will not fit the Cherry MX Low Profile, unfortunately. The slider has a plastic cylinder that goes around the outside of the keycap's stem where that O-ring would have fit.
An alternative though is to make "landing pads": squares of foam with a hole punched through the middle for the slider.
While O-rings and landing pads may reduce noise, I don't think they have
that much effect on ping, really. Ping really comes from the springs, with vibration distributed from one switch to the springs of other switches. I don't think the plate material matters that much either: I have keyboards with PCB-mounted switches that ping.
The most efficient way to reduce ping is to lubricate the springs, but you can't open Cherry MX Low Profile switches that are soldered to a board, not even if there hadn't been a plate.