I'm not aware of a way to set other git parameters globally. Since each global git parameter has the chance to surprise the git plugin with conditions it had never before seen, I'm hesitant to allow a lot of different global configuration settings.
The e-mail and user name settings are required in order to avoid a warning / complaint from git.
The core.longpath setting is a Windows specific setting, and it is accompanied by warnings in the msysgit documentation. There are tests in the git client plugin GitAPITestCase that assert core.longpaths works as expected when using command line git.
You could also consider enabling JGit and using JGit on your Windows machines. The JGit implementation does not have the path length limitations of msysgit.
Mark Waite