Put it all together, used the adafruit i2s hat and speaker suggested in the thingiverse post, and bought some arcade controls off amazon (nothing expensive, just a $25 set). It also houses a pi3 B+ and one of Helder's Retro PSU's with an 8000 mah battery.
Pretty happy with this, although, that back panel does not look to great, I will eventually get a better switch and re configure the placement of the charging port as well. I'll need to re print the back cover too. (i could not get the hinges to fit together, so I will try that again too.)
Otherwise, super cool, and I even printed a second controller for two player games. Here are a few pics.