Softened cream cheese is not optional in a whisk-only batter: cold cheese leaves lumps no whisk can fix. Leave the blocks on the counter for an hour before you start, and bring the eggs to room temperature alongside.
The maple syrup makes this gently sweet, more pumpkin-pie than cheesecake-shop. That is the design, not a shortfall.
Purée versus pie filling: the can must say pumpkin purée (ingredients: pumpkin). Pie filling is pre-sweetened and spiced and will throw off both the sweetness and the set.
Storage: covered, in the refrigerator, 4 to 5 days. The squares also freeze well for up to a month; thaw overnight in the fridge.
This recipe is not yet test-made in my kitchen.