Create an Effect Controller

Putting this on hold because most of this can be done in a particle system already. 

Effect Controller

public struct EffectStruct {
    Effect effect;
    int weight;
}

EffectStruct[] effects;

int minEffectCount;
int maxEffectCount;

float minDelayBetweenEffects;
float maxDelayBetweenEffects;
Vector3 minLocalPosition;
Vector3 maxLocalPosition;
Vector3 minLocalScale;
Vector3 maxLocalScale;
Vector3 minLocalRotation;
Vector3 maxLocalRotation;

bool playInOrder = false;

void PlayAllEffect()
{
    //choose how many effect to play

    // for each effect
    {
        //get delay
        
        //choose effect
        
        StartCoroutine(PlaySingleEffect(effect, delay));
    }
}

IEnumerator PlaySingleEffect(Effect effect, float delay)
{
     yield return new WaitForSeconds(delay);

     effect.Play();
}