I know their is a difference between canon and continuity technically but I think most people use it as the same thing. Also of course something can be good that isn't part of canon or continuity but if you want to create a bigger universe that will be connected and filled with crossovers and you want to do lots of world building then you will likely want things that feel connected over several shows and or movies. Depends on what your aiming for or I guess looking for as a fan.