Instead of using canned pumpkin puree, make fresh puree with pumpkin for a better flavor.
Instead of crushing chocobakes cake into small pieces, roughly chop them and fold gently in batter to make chocolate pockets.
Lightly toast walnuts before adding to batter to get enhanced nutty flavor with crunchy texture.
Streusel tastes much better when the topping is crumbly, therefore add nuts and chocobakes chunks in the topping too.
Overbaking can dry out the streusel so bake at 175°C for around 50–60 minutes, and start checking with toothpick at 45 minutes.