The project used to have Release Goals which, to some extent, defined global
goals for the project. Such goals were proposed at the beginning of a release
cycle and decided by the Release Team. The RT later stated [1] that "whilst
release goals have been useful in the past to introduce archive-wide changes,
[RT] should review whether this remains the case and whether the release team
is really the right place to determine them."
[1] https://lists.debian.org/debian-devel-announce/2013/11/msg00007.html
Still, Debian members need to produce a list of common goals and projects.
Those goals should not necessarily bound to a release. The roadmap will
greatly help us to promote our vision and priorities.