I think it would be cool to have military missions, but use swords not guns. I will probably not be able to host it, but someone else could do it by using
Deadzone's Dueling Weapons Pack:http://forum.blockland.us/index.php?topic=248100.0
SkoopDaHoop's Armor:http://forum.blockland.us/index.php?topic=267675.0
And probably just build a medieval city, or use an already made medieval castle etc.
As for ranks, they can probably just use what they have been using.