Space Battle AI issues

Hi all, I've been working on a space battle simulation, and managed to get quite far into the development, but 'm struggling a bit and hoped somebody smarter than me may be able to help with some a.i. queries?

I've uploaded a video of a space battle here: https://youtu.be/Ga1bfSu7mgA

I have various states Seek, Attack, Evade and Orbit. I'm very happy with progress, but there are a couple of issues ive tried to resolve but struggling:

1. Sometimes a ship flies parallel with its target instead of aiming towards it and firing.

2. Switching from Seek to Orbit (moon) doesn't Lerp smoothly.

3. Ships sometimes get stuck flicking between two states, causing a glitch

4. Battles move too far away from the moon.

5. Sometimes the ships seem to ignore targets

The state machine part of my code is below:

//If target is further than maxDist we lost the target if (target != null && target != moon) if ((target.transform.position - transform.position).magnitude >= loseDist) { target.GetComponent().targeted -= 1; target = null; TargetName = null; }

 if (target == null || target == moon || mode=="Seek")
 {
     Transform temptarget = null;
     // Look for a nearby target - or target nearer than curent
     if (target != null && mode == "Seek")
     {
         temptarget = target;
     }
     nearest = loseDist;

     for (int i = 0; i < enemyShips.Length; i++)
     {
         EnemyShip curShip = enemyShips[i].GetComponent<EnemyShip>();
         if (enemyShips[i].gameObject.name != null && (enemyShips.Length < playerShips ? curShip.targeted < 5 : curShip.targeted < 2))
         {
             distance = (enemyShips[i].transform.position - transform.position).magnitude;
             if (distance <= nearest)
             {
                 nearest = distance;
                 target = enemyShips[i].transform;
                 enemyShips[i].GetComponent<EnemyShip>().targeted += 1;
                 TargetName = target.name;
             }
         }
     }
     // If no nearby enemies, return to moon
     if (target == null)
     {
         if (temptarget != null) target = temptarget; else target = moon;
         TargetName = "Moon";
     }
 }

 distance = (target.transform.position - transform.position).magnitude;

 if (target != null && target != moon)
 {
     if (distance <= minDist && mode != "Evade")
     {
         mode = "Evade";
         randTarget = (int)Random.Range(0, 19);
     }
     else if (mode == "Seek" && distance <= fireDist && mode != "Attack")
     {
         mode = "Attack";
     }
     else if (mode == "Evade" && distance >= fireDist) mode = "Seek";
     else if (distance <= maxDist && distance > fireDist && mode != "Seek")
     {
         mode = "Seek";
     }
 }


 if (target == moon)
 {
     if (distance > 80) mode = "Seek"; else mode = "Orbit";
 }

 if (distance >= fireDist)
     foreach (LaserScript ls in emitters)            {
         ls.firing = false;
     }
 if (target == moon)
 {
     foreach (LaserScript ls in emitters)
     {
         ls.firing = false;
     }
 }

The actions for each state below:

switch (mode) { case "Seek": { // Stop firing cannons foreach (LaserScript ls in emitters) ls.firing = false;

             // If too far from moon, turn towards it, otherwise turn towards target
             moondistance = (moon.transform.position - transform.position).magnitude;
             if (moondistance > loseDist) SeekTarget(transform, moon);
             else SeekTarget(transform, target);

             //Fly forwards
             MoveToTarget();
             break;
         }
     case "Orbit":
         {
             // Stop firing cannons
             foreach (LaserScript ls in emitters) ls.firing = false;

             Orbit();
             break;
         }
     case "Evade":
         {
             // Stop firing cannons
             foreach (LaserScript ls in emitters) ls.firing = false;

             // choose a random target near the moon and peel off in that direction
             EvadeTarget(transform, Moon.targets[randTarget].transform);

             // Fly forwards
             MoveToTarget();
             break;
         }
     case "Attack":
         {
             // Turn towards target
             SeekTarget(transform, target);

             //Fly forwards
             MoveToTarget();

             // If within firing range, start firing
             if (distance <= fireDist) FireAtTarget();
             break;
         }
 }

Thanks in advance