I think combat would be enhanced by the addition of stances to the units during combat. At the moment the nuance is in positioning, but that feels a bit indirect when in comes to controlling an army, I also want to give them clever orders. Each unit could have some aggressive and defensive stances they could pick between to active each turn. Some possible examples of what i mean are listed below.

Aggressive: 

Brutal Attack - bonus dmg when attacking

Swift Attack (costs max move points) - do dmg before taking retaliation dmg

Cautious Attack - bonus def when attacking

Defensive:

Ready to Retreat - retreats if attacked

Surprise Counter (requires cover) - if attacked, do dmg before taking retaliation dmg

Defend Position - bonus def if attacked

Return Fire (ranged) - fire back if targeted by ranged fire.

I hope this helps, thank you for the fun game.