I have created a little 400 lines Python script to make a Studio Clock (multiplexed with a 16x7 matrix). It was a lot of work, but I wanted to see, how far you can go with scripting. The placement of the tracks was made with two aspects in mind. An Easy Pattern, for the scripting and a appearance that looks smooth as it wont have a housing.
The only real problems are (1) you can’t see through the PCB and (2) the traces won’t be green and red. Other than that, my only question is: have you generated the Gerber files to see if everything still looks the same? Since you use line segments everything will probably be OK, but in some cases such as a polygon approximating a circle, the fill code somehow recognizes that the polygon is a circle and then converts that circle into a 16-sided polygon and breaks the design.
That’s easy, use a transparent PCB. If you use conductive ink, it might be possible to dye it different colors. Even without, it would look pretty cool.
For electronics as art, have a look at the work of Guy Marsden, e.g http://www.arttec.net/art/Relevators/DNR22/DNR22.html I quite like practical applications, so I was intending to create some “artistic” clocks, haven’t quite got round to it yet. Well, I made a Tix style clock, but that was just a copy.