CivEffects adds a new reason as well. Since the current implementation of route movement bonus is poor (at best), I decided to reimplement the bonus part. Movement cost will be the slowest bonus from plot owner and unit owner. This mean if you travel through foreign lands, you slow down to his speed. If you want to travel faster, you have to give him the secrets of plot hole fixing (or whatever tech increase road speed) and his roads will improve and you can move faster. However if you own the plot, you don't have to care for the tech level of anybody else, you just move faster. If there is no owner, you don't get any bonus. That should really encourage you to own your own transport network Something like a unit with a function, which can kill cultural influence for a specific player in a plot If it is a hidden unit, like a spy, it could kill off 50 points in one go, risk being detected and if so, possibly killed and/or hurt relations. This could also be used for faster plot takeover if you want to make a cultural takeover to make a fortification next to a city before you declare war. If you own the plot, you can declare war and attack during the same round. Alternatively it could be a unit, which does a task each turn where it moves culture just a little bit, possibly modifies culture points gained by a player. Using units to shift borders could be really important since borders appears to become more and more important as we implement more and more features, which takes borders into account.