We know those issues aren't trivial (especially finish), but it is you who is trivializing the speaker building hobby, it seems to me. As far as specialized baffles go, the only commercial manufacturer that does that in a way that would be essentially impossible for an individual to do, is Revel (they're part of a multi billion dollar company, afterall). However, with a few other innovations, you don't need to have an 8 inch radius to achieve ideal diffraction limiting. And anyone can time align a baffle...