Forgive me, I wasn't looking at it strictly from the pentester point of view but more as an overall security consultant. In implementing a defense in depth security posture I have found that...

I would like to suggest including a cidrmerge util like the one found at http://ftp.heanet.ie/disk1/sourceforge/c/project/ci/cidrmerge/cidrmerge/

Makes the creation of whitelists, blacklists,...