*sniffles* Gah. Where's my damn sequel. You can't give me the whole - another adventure is awaiting - without actually giving me that sequel. D:
Ooooh! Thanks to uisaL for letting me know about the spin-off Kageki no Kuni no Alice (https://www.mangaupdates.com/series.html?id=134552). It was released Dec 2015 (as of June 2016: 3 chapters so far). Not exactly a sequel because different main characters/storyline but set in same universe.
Useful links/summaries/downloads of chapter raws:
http://natsumeislove.tumblr.com/post/148304110598/gakuen-alice-spin-off
http://gakuenalicee.tumblr.com/tagged/kageki-no-kuni-no-alice
Gakuen Alice