I'm not following what you're saying?
Remember a fluid doesn't compress and that the lines are already full. I don't see how line size relates to pedal travel. With the exception of a larger line under pressure will expand/stretch a tiny bit more than a smaller line at the same pressure... so you can get more fluid in it only because the line it's self swells up, and that's inconsequential in a hard line in these sizes..
Pedal travel has everything to do with MC bore size, wheel cylinder or caliper bore, and brake adjustment.
