Jon and I were also thinking of looking into a more automated installation process, i.e. par-installer, par-doc.
The problem really (as my feeling is most installation stuff can be done manually) is how to create an installer that doesn't itself make installation more complex.
We've been looking at CherryPy (www.cherrypy.org) as a possible solution. This essentially generates a python executable with the entire webserver and content included, as is as distributabel as python.
This might make a nice, self-contained, downloadable installation server that appears part web service, par automated tool...
It seems to me that virtually all of OpenACS (from PG upwards) is a candidate for automatic install.