Oh, absolutely.
The late 90s had Will Ferrell, as well as Cheri Oteri, Ana Gasteyer and Molly Shannon, and even Tina Fey joined the writers staff. (They were about to fire Norm Macdonald also, but I guess they can't always get things right)
I was just watching some of those retrospectives Middle12 mentioned above and I was surprised to see they almost pulled the plug on the whole thing right after the twentieth season, just before the new cast arrived. Today it's almost unthinkable to imagine NBC firing Adam Sandler and Chris Farley...