I’m prejudiced against political cartoonists who introduce a regular comic strip. Comic strips done by someone who is primarily a political cartoonist are invariably bad. For example, I think Mike Peters consistently has some of the best ideas for political cartoons, yet “Mother Goose and Grimm” is consistently awful.
I also believe the opposite is true — that people born to create comic strip characters aren’t good political cartoonists. For example, above is the best-known example from Bill Watterson’s brief foray in the genre. Who remembers the Jimmy Carter killer bunny incident?