The Mirror Universe- TNG

Were there ever plans to visit the Mirror Universe in TNG? I would have loved to see a evil version of the crew. I think a Machiavellian and cruel version of Picard would have been awesome. Patrick Stewart and company totally could have pulled that off.

Diane Duane's Dark Mirror was a great book that covered this subject. Each bridge crew member is a dark and twisted version of themselves. It's great. Personally, I would have thought a movie version of this would have been better than Insurrection or Nemesis.

Voyager didn't visit the Mirror Universe either, but at least they had Living Witness that had an evil version of them.

Thoughts?