They really should offer difficult/challengive 4-man dungeons as well. Currently they all follow the same pattern and the only challengive content in the game are the coils. It wouldn't need to be super hard, but at this point any attempts to break the 3x trash 3x boss ez mold is a step in the right direction.

These dungeons should be completely optional, as otherwise people would just cry about progression locks (although I think even story should offer a marginal degree of mechanics to progressively teach people how to play the game).

But, as said. Any content that is remotely hard will get either 'zomgs nerf this' (look; SoF, ppl asking for Landslide to not drop people on TEX) or brushed off as irrelevant if it offers sub-par rewards. Even the coils are majorly overlooked by the casual playerbase of the game.