I'm still trying to get my head around this new trade route mechanic. It seems like there are two choices to be made: 1) Whether to use caravans or cargo ships; and 2) Which cities to send them to. In my limited experience with BNW so far, it seems like cargo ships tend to give you more lucrative cities to choose from, so I have been using cargo ships more heavily. I also tend to just choose the city which gives me the highest gold (usually a civilization's city), unless there is a CS that has a trade route quest. (In my games so far I have always been the leader in science, so I don't usually take science into consideration.) I also never bother with forming trade routes between my own cities, unless I have a new city that is struggling to grow. Just wondering whether this is the best way to use trade routes?