More Stuff!

Pic of Your Mii with Mario and Peach:

 How to unlock: Win all trophies in that class.

Pic of your Mii with all characters:

 How to unlock: Earn gold in every cup, every class.

Alternate Screen:

  How to unlock: Earn gold in every cup, every class.

Mirror Mode:

 How to unlock: Get gold in all 150cc Cups.

Earn 3 Stars 

 How to do: Just do your best and don't fall off the edge and use all shortcuts.