I'd rather see

.../perl/lib/5.x.x/Foo-Bar-0.01/lib/Foo/Bar.pm
.../perl/lib/5.x.x/Foo-Bar-0.01/auto/Foo/Bar.pm
.../perl/lib/5.x.x/Foo-Bar-0.01/my-arch-and-processor/lib/Foo/Bar.so
.../perl/lib/5.x.x/Foo-Bar-0.02/...
[download]

But this is hard to do - the current loading mechanism is overloadable, but we don't have a way to specify what version (except for only), and there is so much psychological inertia in the current scheme.

Perl 6 makes the author name and the module version explicit parts of the full namespace. You can use the short name, or specify whose Foo::Bar you want, and even what version.