It's the out-of-the-box experience that matters:

	Download - Choose where to install - Install - Run

This applies no matter what OS you're using. For example, the Unix
Browser Plugin not too long ago was made of only external modules, and
since the Unix VM does not load modules from the VM directory, you have to
make sure the VM directory is either the current directory for Netscape or
you point an environment variable to this directory. Something every Unix
user should be able to do. You know how many questions I got about this
issue?

Also, the latest Unix VM has a rather complicated directory structure
(no, I'm not talking about the source structure, this is fine) which makes
it rather hard to install Squeak in your home directory.

So IMHO it doesn't really matter if we have external modules or not, as
long as it all is contained in a single archive (zip file or whatever)
containing a simple directory structure and doesn't need any further
setup. And for those Windows users you can easily create a self extracting
archive, right?

-- Bert