I would be happy to see the Hamburg Train system including the regional bahn, s bahn, U bahn and Akn routes driving around Hamburg. I think having multiple routes in one map would also make the game byitself more fun to play because when you play in passenger mode then you could swap trains to go to another destination and maybe in future when technology advances then you could make all the map extensions/DLCs connect together slowly similarly as in eurotruck simulator 2.
If the mapping of the routes is done correctly from the beginning then the routes may well be able to join up eventually. I know in TSx this didn't happen which has caused issues with joining stuff up though
