Form me the smart option is to bring PR in for the Senate.  An elected,  effective,  empowered Senate elected by PR  based on a regional mix.  West-Ontario-Quebec-East    20 Seats each - 10 Men 10 Women  ...your party gets 5% of the vote you get a seat.  Add in 20 Senate seats for direct election by the First Nations and we have a system.  try it out for 3-4 election cycles and then let's look at changing the Commons system.    100 Senators to balance the commons.