I'm part of a team that work on multiple infographic shots simultaneously and we would really like to be able to link to external after effects compositions that could contain components that are being reused on all shots.
In that way someone could setup and animate dummy components within one .aep file and then the rest of the team can link to those components compositions (as if it where footage) and start on each separate shot.
All the while the dummy components can be tweaked and finished and that would ripple out to all the other team members shots.

This is much like how external referencing models in 3d softwares work.

Best regards,
Lars