...Not that the PocketGo d-pad is broken, but I couldn't play a decent game of Pac-Man without the poor guy running up while I was trying to go right. I did a mod similar to the 8bitdo mods - just a piece of tape covering a bit of the direction pad sensors so there is no bumping an unwanted direction when you are trying to go a particular way.
Interestingly enough, covering half (like on the 8bitdos) was overkill - could barely use the d-pad at all. Even covering about 1/4 of each pad, while it seemed to work, was still unnecessary. Basically, if you cover just the inner edge, like in the attached pic - it fixes the situation. It's like just covering the area of the outer ring.
With this, if I accidentally jiggle a bit, the Pac family stays true to the main direction I'm pressing. That tiny bit of area made a huge difference.