I'm currently reading "The Canadian Corps in World War I" by René Chartrand (Osprey Publishing) to get an overview of the subject for a minor project. It claims "the governmentès policy was to enlist French-Canadians individually and spread them among the various Anglophone CEF battalions, in order to pursue cultural assimilation" and a page later "When conscription was voted in July 1917, French Canada was against it, since apart from those sent to the 22nd CEF Bn the Francophone conscrips would continue to be dispersed between the Anglophone units."
I have, very admittedly, little background in this period or subject, but I had thought the Conscription Crisis was because Francophone Quebec did not share Anglophone Canada's desire to support "mother England" in a European war, but these quotes make it seem like Quebec did support the war, but resisted assimilationist policies. So basically, now I'm confused again.
I can't devote time to a full answer, but I can say this is wrong. Like the author says, most French Canadian soldiers were funneled to various french-speaking battalion before seeing combat, and in turn the vast majority ended up as reinforcements for the 22nd battalion, Canada's only French speaking unit. I have never seen or read anything about it is as a assimilation policy, by intent or by accident.
I think the widespread use of English in the Canadian forces certainly turned off French Canadians from joining, but it was not the sole factor in discouraging enlistment. Nor was assimilation the primary motivation behind resisting conscription. As you note, many did not see much value in the "British war" in Europe, as Germany did not threaten Canada or North America.