As I'm sure we all know, A Realm Reborn is by far the biggest road block for new players, and it's essentially the only reason we cannot recommend the game without throwing in a hefty caveat re: how much of a slog ARR is. There's also the problem of players being overleveled by the time they hit Heavensward.
I don't think it would be too big of an undertaking for the developer to pare down the number of quests (imagine an ARR postgame consisting of, say, 20 quests), and possibly even turning a few of the dungeons currently required for story progression into optional dungeons. They could smooth things over with altered dialogue in order to shuffle around some story events if need be.
While they're at it, they could standardize the outdated AoE/mechanics markers in older content to be more consistent with what players will see in the rest of the game.
EDIT: They are officially doing it. They hope to have it done by 5.3