A couple of years ago I collected some of my own thoughts and others from around the web into a commentary on the Haggadah shel Pesach. I took special care to give the seider a definite structure, as in this blog entry, in accordance with the meaning of the word seider, order.
Blogged Divrei Torah about Pesach are all available by visiting this category.
Earlier divrei Torah for Pesach:
Toras Aish 5762 Lekhem Oni and Packing Peanuts
Aspaqlaria 5764 Who Knows Four?