I don't think Sourceforge is a good idea. It is really intended for full scale projects, and is likely to be even less suited to a small module than CPAN.
However, there is a problem with proliferation of modules on CPAN. It's getting harder, in my experience, to find interesting new modules, just because of the sheer size of CPAN. Also, often modules appear with no prior discussion on the mailing list. I don't think this is helpful, at least in general.
Some kind of peer review of CPAN modules would be useful. probably informal, like the XP system here, rather than a formal (and costly) system, like that used in the scientific literature.