Preheat oven to 350°F (175°C). In a medium bowl, mix graham cracker crumbs, melted butter, sugar, pumpkin spice powder, and salt until well combined. Press mixture firmly into the bottom of a 9-inch springform pan to form the crust. In a large bowl, beat softened cream cheese until smooth and creamy. Add eggs and egg yolk, one at a time, beating well after each addition. Mix in pumpkin puree, sugar, flour, pumpkin spice powder, vanilla extract, and salt until fully incorporated and smooth. Pour the cheesecake batter over the prepared crust and spread evenly. Bake in preheated oven for 45-50 minutes or until the edges are set and the center is slightly jiggly. Turn off oven and leave cheesecake inside for 1 hour to cool gradually. Remove from oven and refrigerate for at least 4 hours or overnight to set completely. Before serving, top with whipped cream and drizzle with caramel sauce. Slice and enjoy your creamy, seasonal pumpkin cheesecake.