Love the map and the concept. I especially like how it covers pretty so much of Southern Ontario and is so comprehensive with the coverage.
1 criticism I have is that there are alot of services and it is hard to tell instinctively a REX from a regional service and that on the map, it is hard to tell at a glance which lines go where. I think that you can fix/ mitigate this by reducing the number of unique letters for services that run on the same lines but with different stopping patterns. Taking inspiration from the Parisian suburban system, you could group services that run on the same line and number them to indicate stopping pattern.
A,B => A1, A2
C,D => C1, C2
E,F,G,H => E1, E2, E3, E4
L,M => M1, M2
S,U => S1, S2
This naming system would also allow you to group the REX services with early letters and Regional services with late letters to more easily distinguish between REX and Regional services, like how in Paris, the RER services that run through downtown Paris are A,B,C,D,E and the suburban services that terminate earlier are M,N,O,P, Q,R,S etc. It would also reduce visual clutter on the map by lowering the number of distinct colors.
You don't have to agree with my take but would love to hear your thoughts.
