Inconsistant speed of object following raycast

So im creating a simple game and one component of the game is a greendot following the outside of the level. I got this working using a raycast in the middle which rotates and gives the position of collision the the gameobject.


The problem is that the speed is inconsistant at the moment since the distance between two collisions can be further distance if i have a slope. I also have the feeling that there should be a easier way to get the same result. What are your thoughts?

public class FollowPath : MonoBehaviour {
Vector3 collisionPos;
public GameObject greenDot;

	void Update ()
        RaycastHit2D hit = Physics2D.Raycast(transform.position, transform.up);
        transform.Rotate(0.0f, 0.0f, 3);

        if (hit.collider != null)
            collisionPos = hit.point;

        greenDot.transform.position = collisionPos;

My thought was to have a path the green dot follows. You can place empty game objects at each of the angles the walls make, store them in an array in the dot, and have it move from one to the next. This should give you constant movement no matter the direction, as well as allow more complex room shapes than a raycast would work with.

using UnityEngine;
using System.Collections;

public class GreenDotMover : MonoBehaviour
	public Transform[] waypointPaths;
	int currTarget;
	Vector3 targetPosition;
	public float moveSpeed = 1f;
	float arrivalDistance = 0.1f;

	void Start()
		//Move to the first waypoint, then set target to the second
		transform.position = waypointPaths[0].position;
		currTarget = 1;
		targetPosition = waypointPaths[1].position;
	void Update()
		//Move toward the next waypoint. When we reach it, get next waypoint
		transform.position = Vector2.MoveTowards(transform.position, targetPosition, moveSpeed * Time.deltaTime);
		if(Vector2.Distance(transform.position, targetPosition) < arrivalDistance)
			if(currTarget >= waypointPaths.Length)
				currTarget = 0;
			targetPosition = waypointPaths[currTarget].position;