I find the idea of a sequel interesting, though not necessarily a good idea, but if we're assuming none of the original cast would return, that greatly lessens my interest. Obviously no Robert Preston, and I have no idea whether any of the other cast members have any interest in revisiting this. A sequel with all new characters though, or older versions of the original characters played by different actors isn't of much interest to me. I'm still annoyed with the ID4 sequel for recasting the President's daughter...which is just one of many things wrong with it, but still... It's kind of a shame. The movie did do new and exciting things with CG back in the day, and a sequel that expanded upon the world established by the film could have been interesting, but I fear the window of opportunity has closed. Maybe comics or books or a videogame, where the actors aren't as much of a concern.