I was browsing through the development logs on the Bay12 site and I realized that this game has been in development for at least four years. I realize that DF is a relatively huge undertaking in terms of content and that it is only being worked on by a two man team, but that seems like an extremely long time to be in alpha. I know that there are plans for a lot more additions like the army arc and what have you, but my feeling is that Dwarf Fortress in its current incarnation is a perfectly fun and playable game without any of that stuff.
My suggestion is that rather than spending time adding on all of these arcs and other bloat projects, that Toady et al. just finish up the known issues, and come out with an actual beta release. Then, once it is in its final version (i.e. DF 1.0) They could work on the other stuff as an update or a sequel (i.e. DF 2.0).
Obviously, this is just my opinion. I don't know that much about programming or game development, and I am certainly in no position to tell someone who makes awesome games and gives them away for free how to do their job. But I think that the game has to be 'finished' at some point and I think we may already be at that point.
Just remember: a good design is finished not when there is nothing left to add, but when there is nothing left to take away.