Man, I guess you just don't like Star Trek.
Spock's Brain had its laughable qualities, but it was also a perfectly acceptable cautionary sci-fi story about a society that had stagnated under the control of a machine intelligence. If they had resolved the story some other way than by piloting Spock around like a robot, it would have been pretty good.
Operation: Annihilate! is one of my all-time favorites! Those creepy jelly creatures are creepy. The shots of the seemingly abandoned city are spooky. They killed Kirk's brother in that episode -- BOOM, dead. And the idea that an alien, thoroughly inhuman lifeform can inject cells into your body that grow up your spinal cord and control you, AND that although the aliens look like brainless jellyfish, they are actually a malevolent force that wants to use humans piloting starships to carry them across the galaxy, is a compelling science fiction concept.
Catspaw is another favorite of mine, but why argue the point? It's ludicrous.
The Enterprise Incident was kinda just a Mission Impossible episode set in space ... TV was full of episodes like that at the time. Nothing particularly great about it, but nothing exceptionally bad, either.
As for the Omega Glory, while the whole "alternate, identical Earth" idea was way overused in TOS scripts, it's actually a pretty decent take on the whole Cold War scenario, flipped on its head so that the Federation guy was actually a crazy bastard in league with the Commie Chinese and the guys he was killing off were actually the good guys -- only the good guys had become so debased and ignorant that you couldn't recognize them. The Chinese were the ones that seemed intelligent and sophisticated. And remember, this aired during the Vietnam War, six months after the Tet Offensive.
Bread and Circuses? That was about a world where the Roman Empire survived into the 20th Century technology, with 20th Century technology. They watched gladiator fights ON TELEVISION -- don't you see how that might have resonated with TV audiences in the 1960s? Marshal "The Medium is the Message" McLuhan was publishing his books on media theory around this time. Again, totally valid sci-fi speculation ... really, the lamest thing about it was that they had to shoehorn Kirk, Spock, and the Enterprise into it, instead of letting it stand on its own.
Honestly, I'll argue that ANY episode of TOS has its charms and intelligence ... even something like Spectre of the Gun, which has its farcical elements, wouldn't really be out of place on a show like The Twilight Zone or the Outer Limits, and if it weren't for the fact that they had to have Chekhov and Scotty in it, it would be fondly remembered.
But anyway, with a list of "hated its" that long, I repeat: I guess you just don't like Star Trek.