In medium bow, stir together all crust ingredients except pecans; press into bottom of 9-inch springform pan. Sprinkle ½ cup pecans over crust. Refrigerate while preparing filling.
Heat oven to 300 degrees. Place cream cheese in food processor; process until smooth and creamy. Add pumpkin, 1 cup brown sugar, cinnamon, ginger, cloves, nutmeg and allspice; pulse to combine. Add eggs two at a time; pulse until well-blended. Add rum; pulse to combine. Cheesecake also can be make with electric mixer. Pour into pan.
Bake 65 to 75 minutes, or until edges are puffed and top is dry to the touch. Center should move slightly when pan is tapped, but should not ripple as if liquid. Cool on wire rack 1 hour. Refrigerate at least 8 hours or overnight.
Place ½ cup brown sugar and cream in small saucepan; heat over medium heat until sugar dissolves, stirring frequently. Reduce heat to medium-low; simmer 5 minutes or until thickened (you should be able to see bottom of pan when stirring). Topping will thicken more as it cools.
Remove from heat, stir in ¾ cup pecans. Let stand until cool, 10-15 minutes. Pour over cheesecake, spreading with spatula. Refrigerate at least 30 minutes or until set. Store in refrigerator.