Andy - just an FYI, but Audyssey doesn't set the speakers to large vs. small:
Basically, Audyssey just passes the info to the Onkyo and Onkyo decided that any speaker which produces response below 80Hz should be set to "full range". Audyssey always recommends manually resetting the speakers to small for proper bass management after running Audyssey; 80 Hz is a good default option.
And on the topic of Audyssey... I strongly encourage everyone to play around with re-running Audyssey several times, experimenting with things like mic positioning, speaker position (e.g. toe-in, distance from wall), etc. The results can be subtly different with minor changes, and things like forgetting to unplug the fridge (mine old PoS is like a vacuum cleaner ) or throw the cats in the bathroom can have a large effect.
And quiet really helps of course -- I have a problem with planes or medivac choppers flying over sometimes. Not sure if they do this on the Onkyo, but on Denons you can "Cancel" a measurement if there is an annoying noise which interrupts, and just re-measure that position without having to start the whole thing over.