I don't think it is especially productive to compare marketing/classified range/speed figures that aren't even at a relevant baseline for comparison in the first place. The Oberon's were great boats for the time however, it is rather silly to put them in the same category as a large, cutting edge AIP/Li conventional boat.
As for the addition of VLS, I don't think SLBM's are an especially vital procurement for Canada, but the VLS opens up a lot of potential options. You are able to keep your torpedo magazine largely free from cruise and anti-ship missiles if you can offload them into the VLS, giving you more room for torpedoes or other systems launched from the primary tubes. It seems that only the SLBM is integrated by the Koreans into the VLS right now, however those cells are by their nature very large and can accommodate likely whatever we want, domestic Korean or international weapon systems.
The ability for Canadian submarines to operate internationally or domestically with the option to launch a variety of strike systems very much complicates the equation for our enemies and gives the Canadian govt countless additional options. A hypothetical Canadian submarine stationed out in the Baltic would potentially be able to provide the Army contingent in Latvia with heavy fire support at relatively short notice.