I'm thinking about trying this, as my first photo-etch project went much better than expected. I could always draw on a computer, but never awoke to the possibilities with old photo-etch and other newer technologies such as 3D printing.
I fooled around with catenary in the mid 1970s with the Arnold GG-1. I got it to work in a laboratory setting, but realized it would be impossible to maintain, especially on double track, let along four tracks. And it was not prototypical--my best solution was an upside down plastic Y that clipped onto the supposed carrier wire and held two thin wires underneath--weird, but the two wires (each the same polarity) stabilized things a bit. But it looked weird.
The posts and bridges across tracks seem to be the easy part. It's the stringing between posts--the carrier wire and its supports--that are very problematical. I used the Y for the triangular stiffness.
If anyone else is working on this, please PM me so we don't duplicate efforts. I have plenty of other projects awaiting some attention.