Bring reserved pinapple juice and 1 Tbs sugar to a boil in small saucepan stirring constantly. Remove from heat, and stir in rum, if desired. Set aside.
Puree cream cheese, yogurt, vanilla extract, and remaining 1Tbs sugar in food processor until smooth.
Place 4 angel food cake pieces at bottom of each of 4 wine glasses. Drizzle 2 Tbs pineapple juice mixture over cake. Spoon 2 Tbs chopped pineapple over top. Spoon 2 Tbs cream cheese mixture over pineapple. Repeat layering 2 more times, ending with cream cheese mixture. garnish with sprig of mint, if desired.