Since lorewise Imperial Troops are trained to fight well with each other; where multiple troop types can support their friendly soldiers, maybe basic imperial troops should recieve a certain types of buffs when there are nearby other types of basic units? 

For example, if handgunners are near spearmen and swordsmen:

- Swordsmen gain 20% charge bonus  (Lorewise they would flank or protect the flank)

- Handgunners recieve speed bonus so that they may flee faster to the safety of their friends (15% speed boost)

- Spearmen gain 3 - 4 points of Melee defense

- Halberdiers recieve expert charge defense attribute

It's simliar to the Cathay harmony or Lizardmen skinks and kroxigor interaction, but more deep in terms of buff variety and it's only restricted to the base state troops.