I don't use all the features available either.
It's just that antivirus/antispam are two things that I (and I suspect, many others) who want an SME server (in the generic sense of the word) would need.
A nice alternative might be to include contribs known to work with a particular release on the ISO CD. It would cut down on lots of problems, as most people would then be running the same versions of everything - when an issue crops up, chances are, someone has seen it already...
Just my 2p's worth...