ABS Coated with copper works to - Burnishing the ink before copper bath is the trick..

Here is an ABS grid i coated with conductive ink and found that "Burnishing" with a back of a spoon helps compact the layer and reduce its resistance dramatically.

This was just 15 mins cooking in the electroplating. (had to turn the current down (800ma @2.5V) as once the copper coat starts the resistance reduces YAY ....... I does form quite a resilient copper layer.