ok hows about a hybrid installer?
openACS gurus could just drop in the needed switches like this:
# openacs-init -d /some/random/dir -u username -g groupname -h localhost:8000 ...
that command would just do the install, populate the needed directories, create the database user, shell user, database etc.
and the new users/noobies could just run:
# openacs-init
And they would be walked through all the questions interactively with all the defaults shown. Then everything would be done.