Preheat oven to 425 degrees. In a mixing bowl whisk together granulated sugar, cornstarch and salt. Place sliced strawberries and rhubarb in a large mixing bowl. Add in lime juice then add granulated sugar mixture and toss rhubarb mixture until evenly coated. Set aside while preparing crumb topping.
For the crumb topping:
In a mixing bowl stir together flour, brown sugar, salt and seeds of 1/2 vanilla bean. Add butter pieces and almonds and work mixture together with fingertips until mixture resembles coarse crumbs.
To assemble pie:
Toss strawberry rhubarb mixture once more, then pour into 9-inch pie crust. Sprinkle top evenly with almond crumble mixture (if adding a decoration to pie crust, I recommend brushing lightly with a mixture of 1 egg yolk + 1 tsp water).
Bake in preheated oven 15 minutes, then reduce oven temperature to 350, tent pie with foil and continue to bake 45 - 50 minutes longer until crumble is golden brown and filling is bubbling (during last 20 minutes of baking, I recommend setting a baking sheet on an oven rack below pie to catch any spills, you might not even need it but just in case).
Remove from oven and allow to rest on a cooling rack at room temperature 30 minutes before slicing. Serve with sweetened whipped cream or vanilla ice cream if desired.