A good starting point. A few tips: For the goop extraction sound effect, using AudioSource.PlayOneShot() instead of Play() will make it so the sound effect isn't cut off when you click again before it ends.
Having the save mechanic cost resources is an innovative idea, however I think that at later points of the game it will become very expensive and thus players will shy away from saving their game, causing them to spend time at the end of a session waiting to gather the needed resource, which will only frustrate them.