What would be very good would be a view of the campaign map. On this you could have a view of all the settlements with a toggle option for the owner. Like so:
Owner: <France> You click > and it changes to Spain.
By clicking on this settlement it works like a campaign map, open up the various tabs and have everything fully customiable. Queue up troops and buildings and just purchase them (for free of course) like you would mercenaries. Also things like population should be changeable.
You should also be able to click and drag units and armies to any point on the map. This would be very good. I doubt that it would ever happen though.
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