cosmicpines:

The secrets in the Wheel of Secrets in Between the Pies.

Possibilities would have been (bolded are the answered ones):

Tapestry, Dipper’s name, Blood or Jam?, Mabel’s Secret, The Bear Bear, Gompers, Blendin’s Hair, Mr and Mrs Pines, McGucket’s Song, Monocle, Footbot Dream, Fingers, and Northwests.

…So basically Alex answered all the ones we weren’t dying to know about.