Most of TNG 1 and 2 are reviled just because they're not in the zeitgeist of season 3 or because the show was finding itself... or finding itself re-edited by sexpests and ruining what started out as potentially good stories like "Justice". And many of those I like. Except "Justice" as it became to be, the original premise was far better than what got filmed. I've done reviews on many so I won't go into too much detail for those, with one or two exceptions.
The Omega Glory has a fantastic and horrifying sci-fi subplot where if you beam down and go back up you're crystal. It's unfortunately the weakest "parallel Earth development" themed episode, but the build-up to the reveal of the Constitution wasn't all that bad. Yes, it's contrived but is it all that hate-worthy when you've got fizzbinn on the planet of the gangsters and naziworld where the leader (John Gill) did all except belt out "Rub You The Right Way" and featured the guy who played space hippie leader and so on...
Q-Pid isn't well-loved but Q goading Picard over a woman he claims not to love - and it is a springboard into
Q-Less: More anemic than it should have been, but there's a LOT more in this episode that could ever have been done in TNG in terms of Q being malicious and what happens to Vash is a prime example of that. This isn't the pokey-playful Q from TNG, and even his introducing the ship to a Borg Cube with loss of 18 people doesn't feel as personal next to Vash being hurt by the virus Q put back into her (having removed it when they were on a trip together in the past).
"Plato's Stepchildren" is reviled because of a few scenes taken out of context, usually to attack the show with. It's a high concept episode but buy into it and it's suitably horrific. The Michael Dunn/William Shatner episodes were fantastic. Both gave terrific performances, especially when under Platonian control.
Requiem For Methuselah has a bizarre twist, yet I feel for the characters (the main dude pretty much shaped a lot of Earth's history and the writing and acting sell it perfectly) instead of laughing at what was revealed to be the ultimate toy you could buy at "Fantasy Gifts". Of all the things Star Trek predicted with wi-fi and bluetooth and everything else, nobody wants to talk about the "adult" robots.
Move Along Home is supposed to have the awkward feel because they're playing an alien game and it's supposed to feel awkward. It's a great Quark story as well. If people want genuinely badly written shows, I'd love to namedrop a few...
"Masks" is an oddball but is nowhere near as bad as its reputation.
"Mudd's Women" talks of beauty and confidence from within, not from illicit drug use. Big stuff and decades before "the war on drugs" took off. I still need to rewatch it, but considering 1966's social mores, it did tackle some big issues - even loneliness. That and some other aspects easily could have been handled far better (I remember enough, though I need to rewatch) but for 1966 they still brought up some adult topics for a show people thought was for kids.
"Spock's Brain" is unintentionally campy, and sexist, but tyhe basic premise of stealing a brain to run a computer that operates a whole planet, it's like an inversion of the Borg.
"Let He Who Is Without Sin" is desperately wanting to tell a big story. While it ends up imploding and unsatisfying, there are far worse tales in DS9 lore and LHWIWS does succeed in pointing out Riza is ripe with real problems. That and the dude who plays the bad guy to win Worf over has played quite the variety of characters in his career, making his turn in DS9 even more interesting.
"The Man Trap" - it's got its problems and plot oversights, but in 1966 to show a species that was
not a bug-eye monster but an actual sentient being, having gone insane from a combination of malnutrition and being the last of its species, is often overlooked in favor of cheap shot jokes*. For 1966, it was momentous. If not imperfect.
"Skin of Evil" - the Armus entity is fascinatingly different to the bulk we get in Trek. And malevolent. Yar's death had to be senseless, followed by its cruelty to the others. We are supposed to hate it as well as wondering if any more of the crew will die. It helps if you didn't see the next week's teaser from the week before, which reminds me:
"Symbiosis" - was meant to be aired before "Skin of Evil" as I recall and it's a nice enough episode, with Yar getting a decent speech about drugs based on her homeworld experiences. Yar had a unique background and it's an outright shame that they didn't do more with it and better, it is easy to see why Denise chose to leave the show.

It's also arguably Judson Scott's best Trek appearance (he was in TWOK and Message in a Bottle (VOY) but in this episode there's a subtlety that works rather well instead of being an overt villain.)
"Threshold" - yes, the salamanders and perfect resolution at the end aside - the writers were trying to do something novel with organic material and what happens when they breach a law of physics in such a big way.
"The Way to Eden" is by no means the worst story that changes characters and their motivations for the sake of the plot, and by no means has it got the worst-ever plot - that award goes to Lazarus' alternate identity in "The Alternative Factor". Ok, "Eden" doesn't quite hit a home run (or a single), but the ideas presented, of rejecting all things technology, hinting at paganism, exploiting sex drugs and rock'n'roll several months before Woodstock had, cults, a
synthetic disease that has no cure - the sociological slant is as intriguing as the sci-fi slant, but none of it really gels into anything as good as it should and could. If nothing else, it's another example showing season 3 improving the character of Chekov as he isn't made a mockery-with-Monkees-wig the way he was in season 2. "Backhanded progressiveness" is a term that could be used to describe him in season 2, thank you "TV Sins" for coining that term*.
"Time's Orphan" always got to me, never understood why it was disliked? (yes, the ol' Trekkian standby of "big red reset button" is there, but still... O'Brien got some high concept stories of a personal nature and it's all great sci-fi on a character level because there's character drama that in't bog standard soap opera.)
*