In a large mixing bowl. beat together sugar, brown sugar and oil, until blended.
In a separate bowl, mix baking soda, baking powder, salt, allspice, cinnamon, ginger, and nutmeg. Add to sugar/oil mixture and beat until blended. Add pumpkin puree and eggs. Beat until combined and mix in flour.
Drop ¼ cup of batter, 2 inches apart, on baking sheets lined with parchment paper (or into greased muffin tops pan if you have one).
In a medium bowl, make the streusel by combining oats, flour, brown sugar, pecans, cinnamon, and salt. Drizzle melted butter over the top and stir to combine. Sprinkle over the muffin tops batter.