There will be a BitBox for everything that has an EverDrive. So yes GG, Famicom, TG-16, Genesis, Master Systems, etc. Of course what we can elegantly consolidate into one case we will.
We will also look beyond those as well. Maybe Atari 2600/7800.
Game cases are not great money makers. Our original motivation for the NES case was for the NES EverDrive. We were hoping others would make a case and no one did. So we took it upon ourselves. After seeing the cost of production we decided to make our own case line and make them available to the public to help with the costs. The cases have sold relatively well, but IMO cases have a huge amount of up front cost and overhead to make them worth it alone. This is probably why we were stuck with the UGC as the only real option for so long.