For some reason, I'm led to think the CCL actually played more games against Dayton publics like Belmont and Dunbar than they did the GCL-Coed. Didn't Hartley only play one Co-Ed? There were some years where Watterson and DeSales both didn't play a Co-Ed? Am I remembering this right?
A simple solution would be to base the CCL schedule off what they did last year: double round-robin among the "Big 3", and tell St. Charles to go find some easy L2 points that BH/BW/SFD can cash in on when they play the Broad St. Borromeans. Even easier is get St. Charles to beg entrance into the Mid-State League (where they belong for football) and have them play a 7-game MSL and a 3-game CCL schedule. Cooke, Karl and Zettler Roads can fill in the blanks as necessary.