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The profiles in <nixos/modules/profiles> could in principle provide a great starting point for new users, but we don't really have enough variety. Having some more profiles, e.g. an XFCE one, and documenting their use in a 'quick-start' section in the manual, would be a good improvement.
I totally agree as this was the idea of this profile directory which was first extracted from the configuration CDs.
Profiles are nice as they are providing an abstraction layer and might be easier as a set of common & good & tested configuration set. So, if we are adding such profiles, we should ensure that they are compiling & working well in the test suite.
In addition to desktop environment, we can also make a few configurations to provide common high-level services such as: