For anyone interested, I've patched mock against CVS for the following:
1. Make available configs in the following order, with the latter config
overriding the prior config:
/etc/mock/$CHROOT.cfg <-- Originally, only this was available.
This is in: mock.py-config.patch
2. Make the build.log and root.log prefixed with the name of the srpm
This is in: mock.py-uniquify.patch