no, soundboard is not the ceiling. Theres ear piece mixes to, and ear+audience mixes of shows ive heard.
um, i'm not sure you're right. "quality" is kind of subjective, I know, but soundboard would give you the cleanest, purest signal of the band's performance, and assuming that the record level was good (no peaking, not too quiet) it would theoretically be the best recording you could get. This assumes things like that all the amps and the drums are mic-ed, but at a show as big as Ozma shows tend to be, I'd assume that to be a given. A recording from the audience captures the sound coming out of the PA, which is exactly what the soundboard would give you, except the quality is bottlenecked by the speakers and the room acoustics, which can drag a signal down pretty far. This is of course not to mention the fact that your recording can very easily be dominated by out of key audience singalongs and obnoxious conversation about people we've never met. There are advantages to recording with mics from the audience, like the fact that the desirable crowd noise (a little is desirable now and again, for a good feel) is easier to capture, and the fact that the open air sounds coming from the stage in addition to the PA can often times provide a better mix. I do think though, that such an approach is far less consistant, and as such, I've heard much fewer high quality audience recorded bootlegs than I have heard high quality soundboard bootlegs. An ideal solution, in my opinion, would be to record at least two tracks (one mic-ed in the audience, one from the board) and mix them appropriately in post. If you offered me a choice between the two though, I'd probably plug my recorder into the board any day.
recording from the audience is hard, but Bob does a wonderful job of it with his set up. In my opinion, his bootlegs are on par with almost any unofficial bootlegs I've heard.