We're on record at this blog as being big fans of stuffing meat with more meat, and pork loins are prime candidates. They don't have a ton marbling the way a shoulder does, and while they can be juicy and tender when done well, stuffings can work because they add some extra fat that can enhance the flavor a bit.
You can go with basic bread crumbs or cornbread or something like that, but boudin is basically rice stuffing already. And some pepper jack cheese is a great combination with the flavor of some quality boudin.
The only real trick is butterflying the pork loin, which just requires some care.