Use canned pumpkin rather than prepared pumpkin pie filling.
Almond, cashew, or coconut milk may replace dairy milk in both the custard and glaze.
Smart Balance may be substituted for the unsalted butter when a dairy-free topping is desired.
A few whole pecans may be placed over the crumb topping before baking for additional crunch.
Additional maple syrup may be incorporated into the glaze for a stronger maple and autumn-spice flavor.