Each midi track could use midi channel 1, and in fact that is what usually happens, unless I am working with multiple midi instruments loaded into a single instance of a multi-timbral synth like Kontakt. Even there, I never load more than 6-7 instruments into a single instance of it, so this just never comes up.
When I am recording or even just playing, it is usually only the midi track that is in focus that will get its midi input echo turned on, and therefore its associated midi synth is the only one that I will hear.
Can you please explain how you have things set up that you are in NEED of additional midi channels?
Bob Bone