I agree we owe much to Gene Barry in that he unquestionably helped develop the kind of arrogant, cunning antagonist we saw later on in Robert Culp and Robert Vaughn. But perhaps we should also acknowledge Joesph Cotton, who played the role on stage.
If I can please slip in another plug for Martin Ross' excellent "Columbo" fan fiction site, "Just One More Paragraph"...,
I believe its premiere piece, by our Forum's own Eric Paddon, is the original tale of Dr. Ray Fleming finally emerging from prison to take revenge against his old adversary -- called "Vengeance Is Mine", a great launch to a great site. Reading it, you can happily imagine an aging but still suave and evil Gene Barry in the part.
All "fan fiction" is mainly for fan fun, but this one would really make a great new or final episode, to bring the series full circle after almost 40 years. Great job, Eric!