I do similarly as you.
I write transportation system first,
for example:
AIR for plane,
AIR HELICOPTER for helicopter,
BUS for intracity bus, intracity trolleybus or intracity bi-articulated bus,
BUS AREA for bus, trolleybus or bi-articulated bus of region, intercity,
BUS BRT for bus rapid transit,
BUS CABLE for aerial lift,
BUS HIGHWAY for highway bus ,
BUS MRT for rubber-tyred mass rapid transit,
CARGO for any freight by truck, train,ship or plane,
FERRY for ocean shipping or canal,
MLM for maglev,MLM from
http://simutrans.fr/doku.php?id=en:mlm_dev,
MONO for monorail,
TRAIN for conventional rail,
TRAIN COMMUTER for regional commuter train,
TRAIN HSR for high speed train,
TRAIN MRT for railroad mass rapid transit,
TRAIN SHINKANSEN for shinkansen(新幹線, new trunk line, from Japanese) train,
TRAIN SUBWAY for underground train,
TRAM for streetcar or light rail.
then the second,
city code of the first station is put,
I numbered every city a code so that the route is sorted by city code.
At late,
the purpose of the route and the city name which the first and last station is at,
It may be "city A to city H regional bus line", "city A - city D - city H express train line" or "city A to city H coal truck line".
But I use another number code for intracity route.
So it may be "city A canal line 02" or "city B intracity bus line 63B".