Drain the wheatberries. In a small saucepan, bring the wheatberries and 3 cups salted water to a boil. Reduce the heat to low, cover, and simmer until tender but pleasantly chewy, 25 to 50 minutes. Drain well.
Meanwhile, heat the oil or butter in a small saucepan over medium low. Add the onion and scallions; cook until tender and translucent, about 7 minutes. Stir in the allspice, cinnamon, and rice, cook until the spices are fragrant, 1 to 2 minutes, and then add the currants or raisins, the broth, and salt to taste. Bring to a boil, turn the heat to low, cover, and simmer until the liquid is just absorbed and the rice is tender, 12 to 15 minutes.
In a bowl, combine the wheatberries, rice mixture, and almonds. Stir in the parsley and lemon zest and adjust the salt, pepper, and cinnamon to taste.
If you're planning to use this recipe as a stuffing, it yields enough to stuff about two 3 to 4-lb. chickens, 6 bell peppers, or 10 to 12 tomatoes.