We've waited two years and the only major improvements since the move to 3D have been 1) the location finder and 2) multiple construction selection.
Pay more attention to development. We've also gotten a very much revamped worldgen/history system, for instance. Just because you don't see a change right away doesn't mean it isn't there, or that no work got put into it. Watch a world generate sometime and you'll see.
The problem with this is that the player is not invited to take part in this action at all. If the player were to make the history himself through his actions, that's one thing, sure, and then the history of his actions would be a neat summary a la a succession game write-up. However, the bulk of changes made to DF3D have been, as stated, worldgen, history and other appearance trackers, which happen completely independently of the player and are not the player's toys.
People have long been rationalizing these and other "improvements" as leading up to some grand vision, or that the later, actual gameplay updates will come easier once we have these modifiers in place, but I just don't see it. The player could have wars without any underlying religion worldgen process to supposedly motivate it, for example, and the wounds system was already quite thorough enough. While I admit that giving a beast a skin of iron or whatever will definitely make it more difficult, I don't see how these gameplay concerns couldn't have been handled through some careful tweaks to the existing system.