ThirdPersonShooter-Camera-Script Optimization

So I've build a thirdpersonshooter-camera-script and I need some advice on how to optimize it. I mean it works but it's not smooth. I am still a beginner and this is the solution i came up with.

problems:

• the motion of the camera doesn't seem smooth enough I know there is Lerp() and Slerp() but i'm not sure how to implement it

• i need a better way to limit the camera angle

CameraController:

 using UnityEngine;
 using UnityEngine.UI;
 using System.Collections;
 
 public class CameraController : MonoBehaviour {
     public GameObject pivot;
     public float mousespeed;
     public float lookspeed;
     public Text mouseText;
     public float height;
     public float distance;
     public Texture2D crosshairImage;
     CursorLockMode wantedMode;
     Quaternion targetlook;
     float smoothlook = 0.5f;
     RaycastHit hit;
     float rayHit = 0.1f;
 
     void Start () {
         wantedMode = CursorLockMode.Locked;
         Cursor.lockState = wantedMode;
         Cursor.visible = false;
         transform.position = pivot.transform.position + (pivot.transform.rotation * (new Vector3 (0.5f,height,-distance)));
         pivot.transform.Rotate(Vector3.right + new Vector3(280,0,0));
 
     }
     
     void LateUpdate () {
 
         //escapes MouseLook
         if (Input.GetKey (KeyCode.Escape)) {
             wantedMode = CursorLockMode.None;
             Cursor.lockState = wantedMode;
             Cursor.visible = true;
         }
 
         //rotation of the pivot-object
         if (Input.GetAxisRaw("Mouse Y") < 0) {
             if(pivot.transform.localEulerAngles.x < 357.0f){
                 pivot.transform.Rotate(Vector3.right * mousespeed);
             }
         }
 
         if (Input.GetAxisRaw("Mouse Y") > 0) {
             if(pivot.transform.localEulerAngles.x > 270.0f){
                 pivot.transform.Rotate(Vector3.right * -mousespeed);
             }
         }
 
         //camera collision
         if (Physics.Raycast (pivot.transform.position, transform.position - pivot.transform.position, out hit, Vector3.Distance (pivot.transform.position, transform.position))) {
             transform.position = Vector3.Lerp (hit.point, pivot.transform.position, rayHit);
         }
 
         //rotation of the camera with pivot
         transform.position = pivot.transform.position + (pivot.transform.rotation * (new Vector3 (0.5f,height,-distance)));
         targetlook = Quaternion.LookRotation (pivot.transform.position - transform.position);
         transform.rotation = Quaternion.Slerp (transform.rotation, targetlook, smoothlook * Time.deltaTime);
         transform.LookAt (pivot.transform);
 
     }
 
     //crosshair
     void OnGUI()
     {
         float xMin = (Screen.width / 2) - (crosshairImage.width / 2);
         float yMin = (Screen.height / 2) - (crosshairImage.height / 2);
         GUI.DrawTexture(new Rect(xMin, yMin, crosshairImage.width, crosshairImage.height), crosshairImage);
     }
 
 }
 

there's a second part of the script in the CharacterController Where it rotates the character per Mouse but its basically the same as in the CameraController

feel free to use this script