Well I didn't find any thoughts on the topic, so thought I'd make one myself.
Anyways, once the dwarven kingdom is expanded to include things such as out of castle warfare, might there be an option to expand your own kingdom by sending them out to build their own fort?
There could be several thoughts to the matter
1: You direct the fort/farm/etc directly, such as how you do things in your own fort, making a new fort out as you would your old.
2-3 Basically involve the dwarves building the place themselves, rather then you being able to specifically do everything.
2: You'd have limited micromanagement, rather like a governor sending broad orders rather then specific instructions.
3: You basically just send caravans, and hope for the best at what they make.
There could be benefits as such, like being able to send forth new raw materials and things you cannot find. While one could argue that the dwarf caravan can send anything you want, that may change in the future since they seem to be able to procure everything, even if they come from an area with no real way of getting such.
Some benefits of Dwarfy Imperalism:
1: Being able to gain Tribute in the forms of goods, or coins (Once dwarven economy actually is viable, useful, and has something to offer)
2: Being able to gain goods for a cheaper price
3: Being able to gain goods that you cannot, nor can your mountainholme ever needs to send
Some Cons:
1: You would need to send some dwarves to begin with, and sending a bunch of low class immigrants that dont even know how to mine could end in disaster.
2: Such as the first one, you would need to equip them, bit minor compared to it however, but it depends on whether you can directly control the fort, or if you have to depend on them building it themselves.
3: Dwarfy rebellion, ask to much in tribute/goods then they have would piss em off, eventually culminating with them dividing themselves from you, possibly war/etc.
4: If your not the king, may cause your lordship to begin to question you as well.
This would culminate within several new job types, such as being able to build your own caravaners and such, roadways designed to head to the place would make travel quicker/easier on your dwaves, not to mention safer. I just love huge kingdom type things.

If this has been discussed before, sorry, but I couldn't find anything on the matter, while this is a bit oppertunistic since he's so far away from the matter, I thought I'd like to see some discussion on the matter.