I find it hit or miss. My last game was spain, deity, epic, standard size, small continents, and had about 15 routes to me (150ish gpt). I had to scroll to see them all on screen. They went to full range of cities (the best and the worst) and all were sea routes. All cities had harbors, markets but few had banks if those matter. EIC seemed to do little for AI incentive.
My current game is on large map, mostly inland, and it's hopeless. 2 routes atm around 1700 and have sufficient roads.
Also, roads don't cost gpt in foreign territory (civs, CSs) so build away. I crossed a continent with roads and only paid for 4 of them. Makes troop movement easier too.