Now I know automated level sharing has mixed opinions and I understand the way Legion is that automated level scaling is needed BUT I hope if Blizzard insists on using this technology in future expansions they make it optional like in Witcher III. The reason why i'm not a huge fan is because I enjoy returning to old content to solo dungeons and raids or even to just experience the story from another factions pov rapidly (e.g. i'm currently going through previous expansions as Alliance and enjoy zerging through the mobs. Another reason is RP, in Legion for example we're limited on RP locations due to mobs and aggro. I also miss the variety of having zones by level. In Vanilla, WotLK and Cataclysm we would occasionally have the choice of 2 or 3 zones of our level thus opening a new levelling route for alts. In theory Legion let's us choose which zones but it ultimately still feels linear due to us needing to visit every zone regardless.
Obviously if Blizzard continue with WQs then they need to scale but I do feel beyond that it should be completely optional