Fallout 3 had a very nice mod where you could build your own settlement and with the numerous additions and beautiful locales I find Skyrim is just crying for a version of its own. A skillful modder could integrate quite a few RTS elements into TESV that they couldn't in F3, especially with the overhead map system. And with the NPC fulfilling actual functions within the game world a true economy could be built to support one's Jarl-dom.

I know Arcoolka, of Real Time Settlers, has retired so I am wondering if anyone intends to take up his mantle?

I am actually considering a mod that incorporates this that would also take into account the side chosen by the player. (Imperial, or Stormcloak). I don't have anything solid on it just yet, but I'm getting the ideas worked out on paper. Expect a WIP thread soon.

Look http://www.gamesas.com/index.php?/topic/1283425-pre-wipjarldom-mod/