I don't know if this is an issue but as my experiences I noticed just too few people uses the trains. Now as a train fan this really bothers me. I am trying to connect two most populated districts with railway but only few people (30-40) uses the train. And in order to increase that i demolish the road connection between districts, then they start using. I mean this doesn't make any sense why would anyone want to go to work with cars and get stuck in the traffic instead of using the free train?