Any such project would have to involve re-doing the series' VFX from scratch to make it worthwhile for the consumer, since they were all rendered for 4:3 SD television. Yes, the series was filmed in 16:9, but it was never treated as such during post; hence, all the awkward zooms that appear any time there's a CGI effect on the DVD's. Moreover, as evidenced by the DVD transfers, it seems the show's film elements were not stored well in Warner's archives, there's a whole lot of clean-up work that would need to be done on top of re-composing every CGI effect from every single one of those 110 episodes. Personally, I think such a project would be very much worth watching; I'd love to re-visit the series through such a fresh lens, but unfortunately, I don't think B5 is really popular enough to make such a release worthwhile in Warners' eyes.
I have to admit I've not really been that bothered by Blu-Ray as most movies and a lot of new TV shows look very good on DVD. But I would definitely jump at the opportunity to own a complete box set of Babylon 5 in HD. I hope one day Warner Brothers does commission a new rendering of the CGI from scratch so that this can happen. #FreeBabylon5
There is a complete set available in Region 2 if you have a multi region player, it includes the original 1993 print of The Gathering as well as Crusade and all the sequel films (including Lost Tales). You will still need to buy a standalone copy of the 1998 recut for comparison (it should still be available from some sellers).