If we assume that Parliament has a whipping system (and of course it does) then that's not really a problem.
I guess it also makes sense that some parties would be more prone to bloc voting than others. For instance, the Cooperatives are a group of smaller parties that merged over common interests, whereas the SPP are more of a "big tent" party ranging from center-left to fairly far-left. The Nationalists, too, could be more of a coalition of different interests united by the goal of Pitfarris Nationalism.