Questions:
Salted or unsalted butter?
Light or dark brown sugar?
Can slivers of candied ginger be substituted for fresh? Candied:fresh::raisins:grapes. Also, candied is easier to find and will keep for a long while.
Pumpkin pie spice is supposed to have cinnamon, nutmeg, cloves and ginger in it. You could just use two pinches of the mixed spice, or fine-tune your own blend with the originals.