Each vehicle type is capable of speeds that differ in some degree from other types.
Also, a Formation will be slower than a single vehicle due to the need for the members to keep formation. Companies are slower than platoons which are slower than single vehicles.
When multiple platoons and/or companies and/or single vehicles of different types are organized to advance to contact in mutually supporting positions, or simply in a road march formation, their differing speeds rapidly reduce the organization to chaos.
This creates a huge traffic management problem requiring an enormous amount of otherwise unnecessary micro-management.
The player is supposed to be a Commander, not a military policeman.
I would prefer to be able to select multiple units and formations and specify a single speed for their advance or march, 5, 8, 10, 13, 15 kmh, whatever.
Maybe just let them all have their individual top speeds in the DB, but specify a standard speed for advance, move to contact, etc. in the DB? But in some situations I would want to advance at higher speeds than in others?