King and Castle should have got another series.... Emma Lee should have (a) been done better but (b) got another series... Twin Peaks and the X-Files should have been kept going long enough for the crossoverr episode to be made, for which one of MY short stories was being considered as a basis... My So -called Life could have lasted a bit longer as well....
As for shows that should have been cancelled... top of the list has to be "Friends..." I sat through the pilot, I sat through the first three episodes, and then I learned that it was supposed to be a comedy... its probably funny to Americans, but then they think having a president is a good idea....