I think it would be great to see an episode which had some of the old crew from the original 45. Producers, writers, directors, editors and even some of the actors who were semi-regulars. Maybe they could capture some of the old magic.
They should do 1 more and end it all in a very good way using some of the older cast from the 70's. I like the idea of an original 70's murderer making a comeback. Also Columbo likes the nightlife would be an unsatisfactory way to end it all - really push the boat out.
Hopefully the reality faze is over as i didnt like that idea at all.
If they were to do only one more episode then it should have a finality to it. I think when the episode ends Columbo should retire, whether we know it from the beginng (wouldn't that be ironic) or it is a surprise to us all at the end.