If you use all purpose, whole wheat or regular spelt flour, increase the amount to 2 cups.
I have tried making this with honey in place of the sugar and it is more dense. You could also omit the sugar altogether and serve with honey.
We like a lot of raisins in our soda bread. If you don't, you could get away with ¾ cup.
I used real, cultured buttermilk when making this. You should too.