Assignable Truck Area

So this is an idea for a feature which may even help fix a potential issue with Trains in update 3,
Even without trains though its a neat idea,
Currently we have Areas using Mine towers and Forestry towers that we can assign vehicles to, to do tasks within those areas, but i feature with trains it will expand the distance factories might be built and its already a issue in current gameplay that trucks drive huge distances to do something even tho there is trucks closer by that could do those deliveries, my idea is to make a system that allows setting up an area (That has no size limit) in which that area vehicles can be assigned so they stay within it and operate local logistics without leaving the area too far preventing this issue, this would also prevent the benefit of trains from being negated as trucks could be assigned to only locally deliver (And any trucks not assigned in an area will be able to work anywhere)