I've just built and tested the conventional components, single faced printed circuit board for AVeRCADE. As I've imagined there were some small short circuits due to the proximity of some tracks but easily detectable with a multimeter. When checking with the magnifier glass I've realized that the board should have stayed longer in the etching bath because most of the short circuits were caused by very thin copper connections that remained from the corrosion.

Here are the 1-inch board side by side with the Single faced board. It has roughly the size of an Arduino.

The same firmware can run on both boards. After all they share exactly the same circuit.