Yes, I know, you would have to write a completely different show to do something episodic? I didn't even say anything about number of episodes, I just want more monster of the week style stuff!

Babylon 5 did it pretty well. One complete story, told across 5 seasons of 22 episodes each. Some of the episodes which I thought were filler on first watch turned out to involve critical plot elements in later seasons. I want to say seasons 2-4 were really tightly focused. Season 5 kinda slowed down, mostly because season 4 was written to be a finale in case they got canceled.