If there’s any Glowforge-documented way to convert our product to Class 4 operation, it’s Class 4 according to the CDRH, so unfortunately “convertible” doesn’t accomplish much. (Believe me, we checked!) We can’t offer an at-home conversion kit, either, for the same reason.
I’ll bet that their friendly neighborhood lawyer wouldn’t like that one but then they are the premier sadists - always looking for ways to prevent creative people from having fun.
That’s too bad. Sometimes regulations just get in the way.
Your idea for a middle unit with the exterior of a basic but the innards of a Pro would seem to be problematic. Looked like the innards were what invented a lot of us to go Pro and the pass-thru has become a secondary feature due to its thinness. You’ll have to be careful which innards make it into the mid unit so there’s still an incentive to make the Pro purchase. Or beef up the Pro (thicker pass-thru?) With some additional features that won’t be on the other units.
Oh well, hopper stuff has time to gestate.