This pie looks so good, but I'm not crazy about star anise. What spice might I use instead? A cinnamon stick? This is for a traditionalist, so I...

I think cassia would work too.

You might try whole allspice berries, cinnamon stick, cloves or dried ginger (chunks not ground) or a mixture of the four (easy on the clove if you use it because it is significantly stronger than the others). You could also skip adding the spices to the boil and simmer steps and use a smaller amount (a teaspoon or two) of powdered spices added after the syrup has been removed from the heat to avoid burning it. Good old "pumpkin pie spice" mix would make it easy on you and should play well with traditionalists.

I'm not a big fan of either star anise or cinnamon, but nutmeg goes beautifully with maple. And it shouldn't offend a traditionalist either!

A cinnamon stick should work, or you can probably live it out without much harm.