Preheat oven to 375°. Arrange bread slices in a single layer on a rimmed baking sheet; brush top of each slice with olive oil. Bake 8 to 10 minutes or until toasted.
Combine cream cheese, lemon zest and juice, salt, and 2 tablespoons dill in the bowl of a food processor; process until smooth. Spread cream cheese mixture evenly over toasts. Top each toast with 2 cucumber slices, pressing gently into cream cheese mixture. Arrange smoked salmon evenly over cucumbers. Sprinkle toasts evenly with black pepper and remaining 1 1/2 teaspoons dill.