I never saw Shatner in anything but Star Trek and Boston Legal, but I thought he was thoroughly professional in both of those. The one who had major problems technically was Paul Darrow, Avon from Blake’s 7. Perhaps from too much stage work, but his eyes were always drifting to the camera when he shouldn’t have been aware of it.
TJ Hooker is coming to ME-TV. Shatner as a cop. Not a half bad 80s sitcom.
https://www.youtube.com/watch?v=XONEXKff7sg
I liked Kerr Avon.
https://www.youtube.com/watch?v=SWHLU8fwi80
You missed one of his comedy turns. He was hilarious as "The Big Gant Head" on Third Rock from the Sun.
He played in a couple of the Twilight Zones before he did Star Trek.