First, I have not seen an official ES pronouncement but I think that there are no water trade routes. This in my opinion is about the least realistic feature in the game - trade with colonies was one of THE reasons they were developed, and interrupting trade militarily was one of the main ways countries battled. Would like to see that back in the game somehow.
Second, the land trade route system leaves something to be desired in my opinion. You are kind of taking over a pre-existing Native American route and building Trading Posts along it, gaining from the trade along that route. Once colonies got established, there was trade between colonies and different towns within a colony. Unfortunately the trading units are just animations and you cannot interrupt it militarily except by destroying a Trading Post(TP). I see the reasoning behind how ES did that given the pre-existing trade routes, but I would have enjoyed being able to chase littel trade carts with Hussars, or blow up trains with cannons or Grenadiers.
I think that the following trade system could have worked out well, incorporating some features of the current system with attackable trading units:
(example only)Picture a map shaped like the US, with my 4 person team starting at Boston, NY, Williamsburg, Savannah; the enemy starting at Juneau, Vancouver, San Fran, and LA. There would be, instead of pre-existing trade routes, pre-existing strategic sites or trade sites - sockets like on current trade routes, situated across the map, number of these to be determined by experience. Lets call them Albany, Pittsburgh, Detroit, Atlanta, Denver, Las Vegas, Dallas, Kansas City etc so you can visualize them. My explorer from Boston gets to Albany and makes the first TP there, and a trade route springs up between Boston and Albany - you would have to decide how many trade units to create like the old system(or it could be automatic, but they would be real units). My explorer continues on to Pittsburgh and makes another TP, and the trade route extends. He continues on to Kansas City where the enemy has a TP, My military destroys that TP, and I build there extending my route, and the enemy's route is cut back to some shorter route if he has another TP along it, or stopped if he has no other TP. Maybe allies could build on to a TP already controlled by your team, adding it to their trade route as well(little flag added, or additional building goes up, whatever). I like this concept in that it more realistically simulates how trade developed in the New world, and allows for attacking both TPs and trading units, and would seem to encourage a kind of territorial expansion. Also, upgrades effect your trade routes only. I think a trade system like this could easily be built on the game engine ES is using.
Comments?