I suggest adding "Save as Template" to the Save dropdown.
We already have "Save Remote" and "Save as" there.
Samuel Mehrbrodt committed a patch related to this issue.
It has been pushed to "master":
tdf#99926 Add "Save as template" to Save dropdown
It will be available in 5.2.0.
The patch should be included in the daily builds available at
http://dev-builds.libreoffice.org/daily/ in the next 24-48 hours. More
information about daily builds can be found at:
Affected users are encouraged to test the fix and report feedback.