Well, in some ways it was more complicated; in other ways it was much simpler.
Prior to Westphalia, the borders in Europe were predicated on religious affiliation. This made for a very complicated map. So Westphalia established the idea that a nation could be a superset which included both Catholics and Protestants. This makes for a simpler map -- if one is mapping the boundaries of the newly-established idea of nationhood, and then retroactively mapping that concept onto the past.
However imagine drawing a map of the present, but with pre-Westphalian sensibilities. You'd want to know: where are the Catholics living, and where are the Protestants living? That map has gotten a lot more complicated (even before you try to account for all the Muslims, Jews, Buddhists, Pagans, etc.), and at this point the question hardly makes sense outside of certain bits of Ireland.
Analogously, force monopolies are primarily of interest (at a national level) where territorial integrity is the primary name of the game. But if economic exchange (both competitive and cooperative) between cities were to become the acknowledged name of the game, then although force monopolies would almost certainly continue to exist, they'd be of as much interest as (say) the boundaries between different police departments.
In other words, I suspect the mapmakers of the future draw on the basis of something other than force-monopoly boundaries. This may look more complicated to our eyes -- but we might also look more complicated to theirs.
[edit: grammar]