I have started to re-watch a few of these, and when I say re-watch, I mean for a lot of them the first time in 40-some years, when I was in elementary school. So I am catching up on this thread and it has been very enjoyable to read. Some great points raised.
One thing I have really noticed is the high-contrast, single key light photography sometimes used for the space models. I am so used to seeing well-lit spaceships, this approach is visually striking.
I remember my parents changing the channel on me in "Dragon's Domain," they thought it was too scary. And I guess maybe it was, though I didn't remember it that way. The monster's sound was probably the scariest part. It was like some kind of sick processing machine: Person goes in, skeleton slides out!
It has been interesting to see stuff I didn't understand, mis-interpreted or mis-remembered. I never noticed as a kid how things don't line up with the Eagle interiors (and I had the big toy, of course). On the last one I watched they used the exterior shot where you can see the pilots behind the cockpit windows right up near the top of the nose module, then they cut to the interior and they have about five feet of headroom!
I was sorry to read of Zienia Merton's recent death. As a kid I though Sandra was great, a cool space professional who held her own. And Alan Carter, well, he was the coolest guy on TV in my young mind.