I think part of the reason Spider-Woman was cancelled after just 1 season was because it was separated from the rest of the superhero cartoons on ABC's schedule in 1979. The network placed Scooby & Scrappy-Doo in between Plastic Man and Spider-Woman, which proved to be a momentum killer for action fans. This theory is likely to add fuel to the fire for all those Scrappy haters, but how else to explain how DePatie-Freleng's last series before being sold to Marvel could be such a flop?
One other explanation might be the producers decided to give Jessica Drew (Joan Van Ark, Knots Landing), the alter ego of Spider-Woman, a job in journalism, like Peter (Spider-Man) Parker, except she is the publisher of the fictional Justice magazine, while Peter has been a photographer for the Daily Bugle, going so far away from Jessica's true comics origins, which had been, ah, spun 2 years earlier.
Anyway, Spider-Man returned to Saturday mornings to welcome his distaff counterpart to ABC, but he needs her help to get out of the "Pyramids of Terror".
I remember seeing this when it first aired, and, at the time, I felt this was a little cheesy. Unfortunately, it'd be that way for much of the series.