I would like to see more substance in the sequel, but there are already have 3 writers, I doubt they would add a fourth. It would be nice if they had him on as an advisor of some sort in order to add a little input.
He was a consultant on Babylon 5. Other than the "Planet Killer" concept, which was basically a scientifically plausible version of the Death Star (it kills the planet and all life on it without blowing it to pieces), I'm not sure what other story concepts he invented. While I haven't read anything he's done written, he's an entertaining lecturer and personality. I don't think I'd ever want to meet him though.