I think improving error messages and warnings and default behavior (see my earlier comments on tar and ls) is more worthwhile than writing documentation, as the latter tends not to get read.
+1 for the error messages. Msot of us are used to things not always quite working in the world of Unix. We're used to just taking a look at /var/log/messages and getting a pretty good idea as to what the problem is.
I guess the SELinux troubleshooter goes a long way to addressing this, so maybe there's no point to making the syslog messages a bit better for human consumption.
Ray