There is one issue why I haven't added the https://github.com/nrgaway/qubes-whonix package to https://github.com/Whonix/Whonix/tree/master/packages folder yet. It Build-Depends: on dh-systemd. That dependency isn't available as long as Whonix is based on Debian wheezy. So building Whonix would break when attempting to build the qubes-whonix package.
We could add another hack to https://github.com/Whonix/Whonix/blob/master/build-steps.d/1100_prepare-build-machine#L415 to install it from jessie in meanwhile. Want me to do this?