Alien of the Week shows like TOS and TNG. No season long arcs, no dramas where the events in the episode are less important than the character development [...] SNW was supposed to be that
I remember that during SNW's development one of the producers explicitly stated that while the stories would be episodic, there would be character arcs that ran through the season. So SNW was never intended to be as standalone as TOS or TNG were.