Can you think of any other enhancements? Perhaps using the
aircraft's own lighting to identify the intruder?
Answer: Yes there are a few. Look at this URL
This thread below may be mildly relevant to your proposed DREADLE piece (inasmuch as strobe lights aren't (by regulation) on until you line-up for take-off and neither is the transponder for TCAS considerations). The strobes are blinding for night vision and the transponders are normally Ground-Air sensing off-switched to reduce scope-clutter.
In the phantasmagoria of twinkling ground lighting, I always found that the strobe light was the singularly best (and sometimes only) visual aid in detecting another aircraft on the ground in the middle distance . But of course it doesn't work in fog or heavy precipitation (though it will effectively penetrate mist, light rain and darkness). But it certainly doesn't work when it's not on (and NOT ON because you / he missed the fact that you were transgressing onto a runway). So perhaps another sensible adjunct to the Dreadle System should be this:
" All aircraft are to be fitted with detector-operated strobe and landing lights that will auto-illuminate when entering or crossing a Dreadle-armed runway." (i.e. a runway that has been armed for a landing or departing aircraft, i.e. that one should not be entering).
We all have infra-red detecting security lights that turn on when you drive into your driveway (or exit the front/back door) and similar audio- or IR-activated lights in the rooms of our houses. It's not mind-blowing technology to imagine a short-range treadle-activated transmitter that would illuminate strobes (and so adding to the automated VHF radio broadcast of a "WHOOP, WHOOP, WHOOP ululation followed by: "Dreadle Alert/Dreadle alert. Caution. There has been an unauthorised runway incursion.").
The benefits? Well you not only get to immediately hear about the dull bastard, he gets to instantly know it's him and he gets lit up like a Xmas tree. Avoiding that sort of notoriety should keep both pilots and controllers on their toes - as well as averting the odd accident. And we all know that that accident is just around the next corner. If you don't believe that, you cannot read tea-leaves.