I scratched my head in the past on the problem of running low. Back then, the car was in Algiers and the speed bumps out there were ridiculously high. I resolved my problem with pneumatic shocks and inboard compressor. But this is not applicable for McPherson front. And putting the spoiler back and forth must be a turn off (I’m lazy, that would be for me)...
Why don’t you try to make some kind of “skates” to make sure that if you scratch, you scratch on something more solid than your spoiler. Something made of mild steel connecting on the 2 last fender screws (the front end is quite light, that is certainly enough for accidental light contacts) and dropping lower than the spoiler by a few millimeters. That might be made of square tubing 1” and plate ¼” and look somehow like this:
Just my 0.02$
Louis