Well, this could be a good idea, but actually we already have some problems with train stations who can be saturated with "foreign" traffic. The incoming DLC has taken this into account and so we should not expect this idea, whereas I like it too. You are also not on the good forum, these is one for "Suggestion"
Well, imagine for a bus tourism so. You need to imagine
- Some parking for the tourists bus, which are not the same for cars … Bus hub (monorail bus hub or simply bus hub) can serves as a bus parking lot, to reuse the hub. Space costly, a bus hub can only handle few buses …
- Handling more traffic in the city, because this will generates some traffic in some places, and bus are at least as tall as a heavy truck.
- Better highways connection, to handle the flows of traffic coming into the city and leaving the city.
I let you think about it.