What do you mean by how strong they are?
I'd argue that in Canada, we have a very strong party system. Parties, as much as and often moreso than local RAs choose who their candidate is in a given riding. Parties control who says what - sometimes down to the letter - in Parliament and in committees. Executive control is nearly absolute over the governing party, and party whips exert more control over votes in Parliament than they do in a republican system, such is what is seen in the US.
Party control even extends to the Senate, where nominated individuals aren't really supposed to represent a party, but a region of the province.
Political party insiders and strategists determine who wins and how, who stays in caucus and why, and this pulls our system further away from de facto regional and local representation that would ordinarily exist given the theoretical parameters of FPTP.
If the threat of being tossed from caucus for not voting along party lines didn't exist, for example, I'd argue that MPs would be freer to represent *all* constituents in their ridings, and this would reduce the necessity to modify an electoral system criticized for its inability to be immediately responsive to the wishes of diverse constituencies.
There are downsides to this approach, of course, but the strength of the party system in Canada has its tentacles in "operational" and "management", which I think poison how we view individual aspects of governance and policymaking. Make parties collectives of likeminded folk rather than the bow-down-and-kiss-the-ring monarchies that they are, and we might see the worst of what we hate about governing in Canada improve.