thanks for getting back so fast.
1. changelog. This has been revised with better explanation. I've changed back the first entry as requested and changed the Maintainer field in control. I've added an explanation as to why we need python3-gi
2. I've updated the version field for some of the more important build-dependencies. The package is targeting Jessie as a minimum - although obviously Stretch is the next stable. I've adjusted some of the build versions to accommodate debian derivatives such as Ubuntu Trusty (14.04) where I've been testing also via a PPA
3. Copyright version - updates as requested to include 2016
4. postrm vs postinst ... must have had a brain freeze. Changed to postinst with an explanation in the change log.
If you suggest dumping prerm and postinst then quite content to do-so. Note - I havent found a way to get debhelper to automatically byte-compile the python modules. All the examples suggest I should use distutils in the dh_autoinstall which seems strange and complex to have both an autogen/configure/make/make-install and a distutils-setup.py as well doing much the same thing. Having a prerm/postinst to my mind much simpler to understand/maintain etc.
Anyway - have uploaded to mentors and the mentors web-page now says the linitian is clean.