I think he really did like Adrian Carsini a lot. They sipped a lot of wine, had a meal (even though that was Carsini's set up).

There are a lot of criminals he didn't like; the list could go on forever, but Milo Janus has to be at or near the top. And once he got on the trail of Graham McVeigh he definitely did not like him at all. And of course McVeigh despised Columbo right up to the end until he realized that Columbo was the only one (supposedly) who could save his bacon.

I barely know the later COLUMBO, but I know that he's surprisingly nice to Vivian Dimitri all the way through the story, in spite of the obvious reasons he has for hating her.