Roll out and place bottom pie pastry into a 9 ½ inch deep dish pie pan; place in the refrigerator for 15 minutes.
Make the filling: in a big bowl, combine the fruit, ½ cup sugar, ginger, nutmeg, and lemon juice; toss well to mix, then set aside for 10 minutes to juice.
Mix the remaining 3 tablespoons sugar and the cornstarch together in a small bowl; stir in the mixture into the fruit.
Preheat oven to 400°.; roll out top crust.
Turn the filling into the chilled pie shell, smoothing the fruit with a spoon.
Lightly moisten the rim of the pie shell; place top crust over filling; press the top and bottom pastries together along the dampened edge.
Trim the pastry with scissors or knife, leaving an even ½-inch overhang all around; flute/crimp edges, as desired.
Poke several steam vents in the top of the pie with a fork or paring knife.
Put a couple of vents near the edge of the crust so you can check the juices there later.
To glaze: lightly brush the pastry with milk and sprinkle with coarse sugar.
Place the pie on the center oven rack and bake for 30 minutes; decrease temperature to 375° and rotate pie 180°; slide an foil-lined baking sheet onto the rack below to catch any drips.
Bake about 35-45 minutes until the juices bubble thickly at the steam vents and the top is golden brown; if the top of the pie starts to get too dark, cover with loosely tented foil during the last 10-15 minutes.
Transfer pie to a wire rack and let cool for at least 2 hours before serving.