Saturday is a broken record: no one cares. Fox trots out Cops and America's Most Wanted for their 20th and 21st seasons, respectively. With the exception of College Football on ABC, that's the extent of the original programming for the night. CBS and NBC air repeats of current dramas and throw in Dateline NBC and 48 Hours Mystery for good measure.
I'm relatively sure the networks don't even look at the ratings for Saturday night. Why would they? How about some experimental programming? Something truly different? Use the night as a testing ground. Sure, occasional weekly encores are fine, but you've got three hours (two for Fox; none for the CW) to throw something against the proverbial wall and see if it sticks.
Sigh.