Orange Blossom Water - Adding orange blossom water to the batter won't produce a strong enough flavor to make much of a difference. You'll have to add a lot more, especially since the orange zest tends to over power. You can add it, or you can leave it out and let the orange blossom syrup take center stage in flavor.
Keyword orange blossom cake, orange blossom syrup, orange cake, single layer cake