Gradual Speed Increase with Variable Input

Hi there,

So I'm trying to have my character speed up and slow down by acceleration. What I've got now is working somewhat, but when a small movement is made the player does a little jump. I presume this is because I normalise the velocity vector, so if it was smaller than 1 it causes a burst in speed. The other issue is that with a controller the player stops basically instantly, likely because the controller sends a couple of direction vectors in between pressing a direction and not.

So the issue is I'm using both controller and keyboard input, so sometimes the direction Vector won't equal 1. I'm wondering how to take the input and then accelerate/deaccelerate a movement Vector over time rather than using the direction directly. I've tried a few variations and this is the closest I've gotten, but I'm still using direction directly rather than increasing/decreasing the speed to the maximum of direction.

Any and all help appreciated!

 public override void Move (Vector2 direction) {
     if(direction.sqrMagnitude > 1){
         direction.Normalize();
     }
     
     if (direction != Vector2.zero) {
         // Increase the _currentSpeedNormalized gradually, so the player has to accelerate rather than beginning at full speed
         _currentSpeedNormalized = Mathf.Min(_currentSpeedNormalized + acceleration * Time.deltaTime, 1f);
         _velocity = direction * speed * _currentSpeedNormalized;
     } else {
         // Decrease the _currentSpeedNormalized gradually, so the player has to deaccelerate rather than instantly stopping
         _currentSpeedNormalized = Mathf.Max(_currentSpeedNormalized - acceleration * Time.deltaTime, 0f);
         _velocity = _velocity.normalized * speed * _currentSpeedNormalized;
     }
 
     characterController.Move(_velocity);
 }