Let us have an eye to the buslines - like here [https://opengeofiction.net/#map=17/-37.79534/161.03272&layers=H]
Yes - it is an illegetime child of the streetcar - only in green instead of red. Here you really are mapping for rendering - but you can show your important bus-lines in your city. Name can be given to the line and to the stop. This feature is not foreseen for long-distance buslines from city to city - it is possible, but may be not good looking.
Tagging see [https://wiki.opengeofiction.net/wiki/index.php/OGF:Histor-style] Why "railway"? To take a structure, the renderer know. Why "busline" and not only "bus"? To avoid a key-word for mapping, which may be possible in the future by a standard-style.