Agreed! I think the TW/Shatner absence we discussed a while back - perhaps either he was happy for the break or he simply had no choice in the matter?
Yeah, I think you're right; that was discussed, and not all that long ago. I don't recall the discussions well and am not sure anyone reached any definitive conclusions. I do think that - while I'm no Harvey - I have enough "situational awareness" of Star Trek that I would remember if there was a well-known behind-the-scenes backstory, like for example Shatner's father sadly passing away during the filming of DITD. But maybe not. I figure he was probably happy for the break, and the whole cast and crew were pretty much aware by TW that the show wasn't coming back. At least not until its resurrection in movie form!

(Yay!)
If anyone knows better please chime in.
Regarding McCoy - what episodes do you think he was badly or perhaps not very well written in?
Good question.
As I've gotten older McCoy has failed to resonate with me as much as he did when I was a kid in several episodes, which makes me sad. Now, it was definitely the writing and nothing Dee Kelley did; he was a great presence in every scene and a very skilled actor.
Most examples of what I mean involve tiresome antics fighting with Spock, or even Kirk. For example, the only thing that mars OBS for me - and it's still one of my firm top ten episodes - is that McCoy is a complete jerk to Kirk (heh) the entire show and is completely unhelpful to the resolution of the crisis. He does apologize to Kirk eventually, but the apology comes out of nowhere, does nothing to acknowledge the characters' friendship, and ultimately rings hollow. McCoy then manages to get in the "pitchforks and pointed ears" dig at Spock at the end. It's just extraneous and honestly does the character a disservice.
Then there are McCoy's actions in G7, which honestly should have earned him a court martial along with Boma. (Contrast this with Scotty's smooth professionalism, respect for Spock and the command chain, and rebuke of Boma.) I get that they were establishing conflict and that many of us Star Trek fans found the comparatively Kumbaya atmosphere of TNG boring at times, but they just went too far in assassinating McCoy's character.
The sequence in Gamesters about McCoy - this time regrettably joined by Scotty - openly questioning Spock's search for Kirk/Uhura/Chekov, and loudly and on the bridge no less - is mitigated by the fact that Spock handles it perfectly, and McCoy and Scotty both appear to gain new admiration for the first officer. But it still comes off clumsily.
Final example - and these aren't the only ones - PaS. McCoy is angry with Spock for some reason about his handling of the asteroid situation, but seems less interested in rescuing his friend Jim than getting in digs at Spock. Again, he apologizes with the "we blamed you, well we were wrong" bit but it's TWO MONTHS later.
There are many counterexamples where McCoy was written well, or showed genuine compassion for Spock, in conflict-related situations - Tholian Web, SB, PLW, B&C, and even AOY - but the four I mentioned and some others just bug me a bit.