Preheat the broiler. Using a mixer, beat together 3/4 cup room-temperature cream cheese, 1/2 cup sugar, the grated peel of 1 orange and a pinch salt until smooth. Beat in 1 cup heavy cream until soft peaks form, about 1 minute; refrigerate. Slice 1 pound rhubarb crosswise into 1/2-inch pieces. On a large rimmed baking sheet, toss the rhubarb with 1 tablespoon orange juice, then sprinkle with 1/2 cup sugar and spread in an even layer. Broil about 2 inches from the heat, shaking the pan once or twice, until softened, 5 to 8 minutes. Let cool to room temperature, about 15 minutes. Layer in juice glasses with the orange cream.