For decades, Spirit Airlines has been synonymous with budget travel. From paying for simple things like choosing a seat and bringing a carry-on to enjoying in-flight treats, Spirit has long offered barebones options to customers looking to get to their destination on a dime. All that looks like it's about to change, however. On July 30, Spirit announced a major overhaul of its ticketing tier system that will radically transform how their customers travel. With four different ticket options to choose from offering a variety of flying experiences, there's something for everyone at every price point. At the base level is the Go fare, which looks most like the typical Spirit trip today. You get a ticket and a personal item included, but you'll need to purchase things like seat assignments, checked bags, and snacks separately. And if you'd like to pay for a carry-on, you won't be able to, as Go customers won't have the option and will have to purchase a differen...