What would be the effective duration that the individual tasks take when attempted in post-worldgen, will the events themselves (not traveling) be near instantaneous and travelling itself be static, or will obstacles such as negotiations, intermittent stops (sleeping, acquiring rations, slowing by weather, travelling offroad, confrontation, injured dwarves and treating injured dwarves) hinder mission time any? Will any of the above affect morale and stress of the dwarves themselves in any manner?
Will squads or individuals pursue personal interests en route to their destination, or change their plans in the event that the conditions of the mission change the situation initially planned for, or in the event that squad members come across a situation or circumstance that inspires their ambition?
As increased interactivity with the outside world increases, the dwarf-mode adventure-mode time discrepancies begin to become more significant. How do you plan to address certain situations where the discrepancies are pretty significant? For instance, on a slightly large embark at a distance of a handful local regional tiles away, if you send out an expedition, it will take significantly longer for your dwarves to get off of your front lawn than it will take for them to cross the geographically longer distance to the site.
I imagine this can be mitigated somewhat by allowing dwarves to leave and re-enter the site via minecart, in particular in the instances of the lack of (and before the implementation of) inter-site minecarts: the only purpose of the minecarts being to move the squad on to an abstract close off-site hub where they can begin their travels, unhindered by fortress time dilation.