Loved this!
I lived in Alabama during my early childhood years, can't say I ever said "big ol'" anything, though I do remember saying "I'm fixin' to!" a lot.
IMO, "y'all" is one of the greatest, most useful words in southern English.
Last, about those stores that sell bait, movies and food, I remember one up in northern New Hampshire. I rented the movies and bought food, too. It's okay, as long as the bait isn't in the same case as the food!