I think its not that bad. I mean, man, its the mid 60s, and probably not a very well funded TV flick. I even like the story, its this typical 50s and 60s scifi stuff. When the writers still talked about ideals and the screwed up society, not about super kitten vs lord evil dude over and over again. Most of my favourite movies were made back then, like New York 1999, Dark Star, Logan's Run, Silent Running ect.
Today its all big CGI and nothing behind it.
So I wouldn't judje this episode too harsh, compared to other stuff from that time. We are just used to a different kind of presentation today, so it seems a bit weird to us now. Hell, I even watched movies that I had in memory as super cool - and now I find them pretty lame.60 years is a long time...