Aligning an object to both the surface normal and the input direction at the same time

I currently have a utility script that looks something like this:

  public class Utilities
     {
         /// <summary>
         /// Returns true if the thumbstick is pulled or if the arrow keys or WASD keys are pressed.
         /// </summary>
         public static bool LeftThumbstickAxisIsInUse()
         {
             return Input.GetAxis("Horizontal") != 0 || Input.GetAxis("Vertical") != 0;
         }
            
         /// <summary>
         /// The vector direction that the analog controls are being held in, normalized. 
         /// </summary>
         public static Vector3 AnalogDirectionVector()
         {
             return new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical")).normalized;
         }
 
         /// <summary>
         /// The direction that the analog controls are being held in around the direction 'upwards', as a Quaternion.
         /// </summary>
         public static Quaternion AnalogDirectionQuaternion(Vector3 upwards)
         {
             if (LeftThumbstickAxisIsInUse())
             {
                 return Quaternion.LookRotation(AnalogDirectionVector(), upwards);
             }
             return Quaternion.identity;
         }
 
         /// <summary>
         /// The direction that the analog controls are currently held in, in euler angles around the direction 'upwards'.
         /// </summary>
         public static float AnalogDirectionEulerY(Vector3 upwards)
         {
             return AnalogDirectionQuaternion(upwards).eulerAngles.y;
         }                  
     }

In my character's 'look' code, I have the following method:

 private Quaternion SlopeAlignment ()
     {
         return Quaternion.FromToRotation(Vector3.up, hit.normal);
     }

My goal is to allow the character to align itself with a slope to move across, up and down it using directional input from the arrow keys or a thumbstick on a controller, or otherwise. When the character moves to a section of ground with a different surface normal, it should align itself with the new normal and continue to be able to move in all directions across the slope without rotating locally on the X or Z axis when in motion, unless the surface normal changes.

Any help or advice would be much appreciated.