JMS has been trying to distil and bottle it unsuccessfully for years. He told an amazing five-year story over B5's first four seasons*, but then each time he goes back to tell more stories in that universe it becomes more and more clear that he can't come up with anything capable of standing next to what he's already done there.
*Context: they crammed the planned s4 and s5 into s4 because they thought they would get cancelled, but then they got unexpectedly renewed so JMS had to write what was effectively an epilogue s5.
Most of the planned season 5 wound up in season 4, but there was so much that some of it did wind up in the actual fifth season. Most of what made it wound up in the back half, which is significantly better than the final season's front half.
I’d be happy if the show could be redone with modern technology. The CGI that was cutting edge when B5 first aired now looks very dated and I think it’s hard for younger prospective fans to get into the visuals.