I tried to do a complete switch from FOUserAgent to logger in the images package, was not able to (there are still other cases the FOUserAgent is actually being used.)
Glen - I havent looked at this in detail, but my understanding of the FOUserAgent was the place holder for any user configuration, e.g. baseFontDir, baseImageDir, etc. So by changing all FOuserAgent arguments to loggers, are you excluding the possibility of code in the images package from accessing any user configuration, e.g. baseImageDir?