If implemented -- I'm not sure whether it should -- then:
(1) Rally-points only make sense in combination with auto-production: related to a specific unit in a specific territory.
(2) Rally-points should only be applicable in own territory and pointig to a city as destiny: no attack function, just to gather units for further mobilization.
Always having in mind, that AW is "just" about producing and moving the right units, the right moment to the right places... besides making the right diplomatic moves (based on principles and/or opportunity). In this sense, rally-points should provide "only" automatization, very much like auto-production.
Cheers,
CD
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