After talking with Mike Gurley, our local Canon rep, about my image quality problems (he got right on the case) I tried, at his suggestion, the dreaded Canon RAW processing software that comes in that disk with the camera that none of us has ever loaded. Here's a badly underexposed shot (there's correcting for highlights, and then there's just blowing it) and what the various RAW converters have to say about my ineptitude.
The Canon conversion is a good salvage job. The Adobe conversion looks just dreadful. The problem, however, with leaving an Adobe pathway is that, as far as I know, every other conversion workflow leads to a tif or jpg output. In Adobe there's no need to convert files after correction, though I archive in dng format so I don't have to keep tabs on that little xml sidecar. It would be a big disruption to my archive pattern to have a second conversion path.
I'm open to other ideas. One problem I had was finding a converter that works with Mac OS 10.4 (I've resisted the upgrade to Leopard, as I don't know what all will stop working if I do). I'd love suggestions on what else to try.