There is no definitive list of features, nor release date. Since it’s a volunteer project, having a fixed schedule is rather moot.
There is a roadmap https://docs.kicad.org/doxygen/v6_road_map.html which may give some clues. Otherwise, there is a thread here Post-v5 new features and development news and general hanging around the forum.
Of course, if you were to simply ask about specific things you are interested in you might get specific feedback.