At the risk of offending JMS by comparing B5 to Star Trek, All Good Things is a better model for this kind of story; where the character goes back-and-forth between alternate timelines and has to figure out how to work in all three to fix the situation.

Maybe Walter Koenig isn’t up to it anymore, but if they were going to do another B5 story I would have liked to see them bring him back. As far as a new B5 story that would have fleshed out some of the stuff they teased at the end of the original series, that would have been my pick.