Totally agree with Jon, Shadow and Black Bird... There's really no point in those remasters for the fans (except maybe for the completists) as they already have the albums. Trying to sell them the reissues again is disrespectful
What Sony could have done is some kind of retrospective of the studio albums (no need for the "live" albums apart from The Concerts in China). I doubt there are many outtakes, but they could have included a rough mix of the albums for example that shows the work in progress. Also maybe an accompanying booklet that gives some insight and analysis on the albums, placing them in their historic, technical, trend and commercial contexts, etc. A bit like what is done for releases of classical music, where they often have interesting liner notes. Jarre's chronology (no pun intended) is a history of electronic instruments, so there would be plenty to write about.
Since JMJ has been interested in 5.1 they could have made 5.1 mixes of the old albums. I'm not a big fan of such treatment, but at least that would be something a bit different from a remaster that's merely going to be the same as the original, only compressed and with the volume cranked up to 11.
Or they could have made comprehensive compilations of all the remixes and alternate versions that have been released throughout the years and are hard to find on 7", 12", maxi-CD, etc., again with some background info on those. Granted, this stuff is for fans only, but hey.
But all this is more work and research than remasters...
Don't get me wrong, I'm not bitching about it, everybody's trying to make a buck, right? it's just seems to be a missed opportunity. Oh well...
Concerts: 2017: Upper Darby < 2010: Lille, Liège, Paris < 1997: Lille < 1990: La Défense