Plurality voting systems (ie. First Past The Post) not only disenfranchise voters, but also distort the makeup of Parliament. Parties are encouraged to speak to appeal to a narrow base, because winning in an FPTP election is often as much about "vote efficiency" as it is gaining significant voter support. In other words, a party who sees they can gain high vote efficiency in some regions of the country will tend to concentrate efforts, and create policies, that benefit those regions. The government that is inevitably formed will place much more emphasis of ridings and regions where it can gain the most efficiency, and have the best shot at electoral victory next time around.
Only six governments since Confederation have won majorities with over 50% of the vote. FPTP is fundamentally incompatible with an electoral system of more than two significant parties. Rather than inevitably see are parties march towards a muddy American-style two party system, it would be better to pick a new electoral system that encouraged a healthy multiparty democracy that better reflected the will of the voters.