Reducing overhead while controlling many units

Hello,

I'm making an RTS game that aims to have a LOT of units on the screen at any given time.

Right now, in the early stages, I'm getting heavy FPS drops when commanding 100-200 units on screen.

Using the profiler, I checked where my lag is coming from, and it's coming from the update function of each individual unit. The update function of each unit is as follows:

     void Update () {
 
         if (isSelected && CameraControl.commandIssued && completedCommand && !isActive)
         {
             computeDestination(CameraControl.destination);
             isActive = true;
         }
         else if (isSelected && isActive & !completedCommand && CameraControl.commandIssued )
         {
             computeDestination(CameraControl.destination);
         }
         else if (isActive && !completedCommand)
         {
             moveToLocation(globalMoveDirection, CameraControl.destination);
         }
         else
         {
             //idle
         }
 
     
     }

Here is that function being called each frame:

     public void moveToLocation(Vector3 movDir, Vector3 destination)
     {
         unitCharCont.Move(movDir * Time.deltaTime * unitSpeed);
         distanceFromObjective = Vector3.Magnitude(transform.position - destination);
         if(distanceFromObjective < 0.5f)
         {
             completedCommand = true;
             positionComputed = false;
             isActive = false;
         }
     }
 

Broken down, the code basically says "when a command is issued, compute my destination a single time, then update my position using CharacterController.Move() every frame until I reach my destination.

Is there a more efficient way to move units? I.e. does CharacterController use more resources than a RigidBody? Or, does anybody have any ideas as to how I can cut down these 200+ calls per frame to 1 call, and control the selected units as a single pack? I'm sure I could get creative, but I'm reaching out in case anybody has encountered this and has a good solution.

Thanks for any help! Vranvs