Maybe alter the concept in such a way that traditional military units are still allowed(maybe futuristic variants?) but the "super" soldiers/vehicles are the insect/animal inspired vehicles. This would give you more freedom of which units you could use and would also create an interesting world. You could then have scenarios where a military base has to be defended (add units who fight along with you) or could go on missions to destroy/capture an advanced military installation that threatens the well-being of the world. Another game mode could be just to have some battle take place in the forest, battlefield style. Where a countdown is done with units killed or capture the flag with a countdown.
Behavioral changes I would make to the demo:
• Rather use a camera follow script that is smoothed than the current one attached to the gameobject/transform. The abrupt movements with the terrain are a bit too much.
• Allow the user to aim with the mouse cursor. Or is that there? Couldn't see how to do that.
• Use an arrow on the minimap for the player to quickly judge their orientation or make it more clear.
Other changes:
• Some background audio would be a nice touch.