Audio mixing and distribution

Given some number of potential audio sources (in digital
form, of course) and some other number of potential "sinks",
if you assume each sink has preferences for how the various
sources are presented/mixed, is the "most manageable" way
of designing the network to configure each source for some
nominal "0 dB" output level and install a mixer at each
sink with associated gain?
Is there ever a reason to allow for gain/attenuation of
the individual *sources*?  It seems like this invites
a "squeeze the balloon at both ends" sort of scenario;
you tweek one of the source gains and then have to run
around tweeking the associated mixer input on each
sink.
By contrast, even if EVERY sink wants a particular source
attenuated (coincidentally by the same amount), they can
still make that adjustment "locally" without impacting
other sinks on the network.
Additionally, if the sinks are multichannel, is it best to
provide a follower for each channel so they can be independantly
set (vs. a "balance" of sorts).
[Think about why it is NOT done that way in consumer kit]