Overall, 3-5 are the strongest IMO. Season 6 would be counted among that group, since its good eps were just as good as anything in 3-5. However, while 3-5's bad eps are just boring, season 6 has the ridiculous "A Fistful of Datas", and the downright
abysmal "Rascals" and "Man of the People." So it has to slide down a notch.
A random sampling of favorite eps from s 3-6 (this is by no means a COMPLETE list; there are more good or great eps from those seasons than the ones listed here):
3: "The Defector", "Yesterday's Enterprise"
4: "Remember Me", "The Wounded"
5: "Conundrum", "The First Duty"
6: "Face of the Enemy", "Frame of Mind"
Season 7 was a mixed bag... I did think it had a handful of great eps (some of my series favorites are in s7), but it did have several ranging from mediocre to boring to awful. Overall, I agree that they seemed to be running out of steam, and it was a good decision to end it where they did.
S 7 standouts include "Gambit", "Parallels", "The Pegasus", and "Lower Decks." Oh, and "All Good Things...", of course...
Season 7 was maybe slightly better than season 2 on the whole, in terms of episode quality, and didn't suffer from the awful aesthetics of early TNG (everything before s3, basically). Season 1 was horrid; it peaks at a small group of eps that are "not too bad".
I don't get the association of cheesiness with quality. I could see you'd appreciate the CHARM of it but still like the more polished seasons better.
I agree with you here. Cheesy can be sort of fun, but only when it's existence doesn't take away from something that I feel should be
not cheesy. i.e. when I watch the animated '86 Transformers movie, I expect some serious 80's cheese, and it amuses me. Star Trek, IMO, should not be cheesy; when it is, it's failing.
And I don't get the comparison of early seasons of TNG with TOS.
The perception that TOS was "cheesy" or "campy" is a misunderstanding of the look of the show or of the different social attitudes of the time. TOS was regarded as serious sci-fi in its day, not on the level of Adam West's "Batman."
TOS hit the ground running whereas TNG stumbled a bit before finding its footing.
I agree that -
for their time - TOS got off to a gallop and TNG very much stumbled at first. However, it seems you're referring to creator intent and to how each show should be viewed WHEN they were each airing. Which is fine. I can't speak for anyone else, but when I talk about the "cheesiness" or "campiness" of TOS, I'm simply referring to qualities that I see when I watch the show and attempt to enjoy it (and, in fact, those qualities often make it harder TO enjoy it). Certainly, it was serious sci-fi in its day, and (even now) doesn't come off NEARLY as ridiculously cheesy as something like the Adam West "Batman" show, and we can have a conversation about WHY some of the elements are in the show, but that doesn't change what I see when I sit down and
watch the show.
I was referring to the music with these silly synth textures and how several episodes end with a cheesy joke. Things of that nature. Naturally, since both shows were created by the same person, there would be similarities in the production. For example, like any genuine musician or artist, their influence is apparent in every piece of work they do.
These are things I also see in season 1 of TNG, and are among the reasons I think season 1 is the weakest.

The bolded part, in particular... so many of those endings (in both s1 TNG and in TOS) were
so lame it was almost painful.