Nah, that's too easy Warren
I'm going for a swinging pendulum hammer, held in place by melting ice, swinging and knocking a tall Polynesian transwoman (In heels!) from a balcony with said rope for the swinging cut by a tied up razor wire on the ceiling. The hammer then also goes flying out the window but has a parachute on it which opens seconds after release which helps carrying it out to the ocean due to the Santa Ana winds (Guessed at occurring by the sundowners which precede them). Two pullies also instantaneously retract both the rope and razer wire out of sight in the ceiling within the building. The victim's body lying dead in the garden of a fancy house during a party which has yet to see Gary Coleman's character arrive at since he is still on live television during a national Telethon call in to help the orphaned children of dead servicemen and women.
It would seem that a tall, strong person had struck the victim terribly hard with a blunt object which caused them to fall to their death. They then must have escaped the party unseen with the murder weapon and everyone at the party is accounted for and no weapon was found on the premises.
The only thing linking the two is that they were both supposed to host a new show at this house in a month or two, a show which was a reality TV programme based on dating multiple people before choosing that special one.
Columbo was stumped!
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Columbo would have solved that one by seeing the footsteps on the step stool or figuring out he used stilts, Siggy.
"Please vote to preserve the unique character of Warren…" - Robert Duvall

Oh, OK, but I was going for the whole diversity, equality and inclusion angle Woody
Gary's character would frame a murder so that it could only have been done by someone taller. He'd have nothing to gain from it, if anything it could be destructive to his career, and he had a perfect alibi for when the murder took place too
But Columbo still manages to figure it out because you can't stop a Basset Hound's nose when it gets the scent
In the end Columbo thanks him for being so imaginative and seemingly doing the world a favour. But the law's the law and he has to take him in..
We could maybe end on a freezeframe of them both laughing, Columbo cigar in hand and Gary's character pulling a funny face
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That would have been a cool and inspired bit of stunt casting.
You've seen Guy Standeven in something because the man was in everything.

Gary Coleman could have been awesome!
"Whachu talkin' bout Columbo?"
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Anthony Zerbe played a victim in one of the Columbo TV movies, but alas never played a killer. He would have been great as the killer in a Columbo TV episode from the 1970's.
You've seen Guy Standeven in something because the man was in everything.

Christopher Lee would have been great. He may have been to obvious to cast though.

It's such a great formula that I think anyone from Barry Corbin to Charlie Sheen would have been great, the list goes on and on.

Charleston Heston or Clint Eastwood.

Good call on Anthony Perkins. And I wish Vincent Price could have had a role as a killer. But how about Robert Shaw from "Jaws" fame? Imagine Columbo taking him on! Such a shame that he died before he could further his acting career.

In you opinion, George Wendt's character was not natty, upper class or snobby?
You may cross-examine.

I think about this often, and my top three choices are: 1) Orson Welles, 2) Cary Grant, and 3) Fred Astaire. In my opinion, the strongest episodes are those in which there is a strong difference between the murderer and Columbo: natty vs. slobby, upper class vs. middle class, snobby vs. personable, etc. That is the dynamic that made the early shows work so well, and it is missing, unfortunately, in many of the later episodes (for example, using George Wendt as the murderer just doesn't work!)

Alan Rickman
"I used to be a detective like you, but then I took a bullet to the knee."-Law & Order: Dragon Squad

You probably know this already, but Vincent Price at least got to guest-star in 1973's "Lovely But Lethal" episode.

Would have loved to see a few British stars, including Ian Richardson and Ian Bannen.
50 Is The New Cutoff Age.