I prefer the following for a RSEQ/OUA merge:
Tier 1 (6 teams) : Laval, Montreal, Western, WLU, McMaster, Carleton* 3 teams x 2, 2 teams x 1, Winner vs Can West for Vanier Cup
Tier 2 East (5 teams): Sherbrooke, Concordia, McGill, Ottawa, Queens 2 x 2 teams, 1 x 2 teams, 2 interlock with West
Tier 2 West (5 teams): Guelph, York, Toronto, Waterloo, Windsor 2 x 2 teams, 1 x 2 teams, 2 interlock with East

* perhaps replace with Guelph and move Queens to the West
Winner of Tier 2 replaces last place team for Tier 1 the following season.