I suspect you would avoid things that could be automatized, and rather focus on something that has relatively high margins due to either customization/personal touch or fit & finish reasons. It probably helps if the overall market isn't massive too, just plenty big enough for a small team.
e.g. find a sport or hobby that requires tools/components that can be manufactured in your 2-car/2 person setting. Then give them customization or very high quality. CNC is basically commodity now, as are 3D prints - you need something outside that box I think, or at least have it only be a component of what you are doing.
e.g. find a sport or hobby that requires tools/components that can be manufactured in your 2-car/2 person setting. Then give them customization or very high quality. CNC is basically commodity now, as are 3D prints - you need something outside that box I think, or at least have it only be a component of what you are doing.