Babylon 5 is my favorite work of fiction. I've watched it many times throughout my life, and it has taken on different meanings for different seasons of my life. It is a remarkable show.
If you haven't ever watched it, give it a try. The first season takes a little while to get going, but the overall story is just incredible. It was a lot of firsts: the first television show to use CGI. The first US show to be filmed for 16x9, knowing that DVD and HD were coming (although that didn't quite work out, as noted in other comments). The first American show to write the larger, five-year story arc entirely in advance.
My favorite shows have three elements: a story with a beginning, middle, and end; interesting characters that grow and change over the course of the story; and they have to stick the landing. Many shows like Game of Thrones and Lost were fun rides but never quite sealed the deal.
Babylon 5 does the best job at these I've ever seen. The Shield, The Expanse, The Wire, Six Feet Under, and Buffy are other personal favorites. If you like those, give it a shot!