Shipments were the AoE contemporaneus equivalent to CnC Generals abilities or Company of Heroes Call in’s. However, shipments still use an anticuated spawn system in the case of units, as they spawn and move to the building military rally point, creating additiona steps for the player in order to get the units where they want.
Most of the time, shipments will use the town center as a spawn point, which by default places both military and economic rally points on the same spot. Obiously, the player can get around this by customizing his controls and using the already convoluted hotkeys
There is also the case of building wagons and their equivalent. The player has to wait for the wagon to arrive and then select the building icon and place it on the map.
This could be solved by bringing using a system where the player can select the card they want to use and then place it on the map. When the unit arrives to its designated spawn point, then they automaticaly move to where you placed them. In the case of building wagons, it could use an added function to build the structure once they arrive to the designated point.
In one hand, this could be used to reduce the micro tax on the player, as it could be manouvering on the map and call reinforcements on the fly, on the other, it makes it less likely to lose building wagons or to let them idle in base, just point, click and forget