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For fans that have been around since 2009, until mentioned otherwise, you might as well assume that these features are postponed indefinitely. Citing bandwidth issues and other concerns for holding off replays and perhaps more questionable reasons for holding off sandbox mode, Riot shifts its priorities to other endeavors.
Riot Games has stated that they will be focusing on tech optimization as well as paying off debt largely from hosting thousands of servers and from creating the hardware and software architecture to compliment said servers. In addition, the ever elusive client rework is said to be worked on in the near future.
Riot has also stated that they will be working on increasing quality of first-party content and narrative both for lore and eSports, and making the game generally more enjoyable with friends, although the details on this are vague. While there hasn't been much digging into the specifics, Riot states at the end of the article that they will be a bit more open with the fanbase in terms of direction and current work projects.
You can read Riot's article here.