It really helps to fall asleep. Especially when it wanders visually rather than verbally. I indeed force it into inner (imaginary) visual wandering to fall asleep faster - conscious (even mindful in the beginning) "daydreaming" naturally turns into deep sleep then. It probably also is nice to have some mind wandering during the day if you are not overly prone to that naturally. For me, however, mind wandering seems a debilitating form of procrastinating against the entire life.