The thing that launched off my creating this thread was a feeling that in a great many ways, "The Cage" is Star Trek as Roddenberry intended it to be before the reality of commerical interests made compromises necessary.
I'm not sure what you mean by that. The changes made between "The Cage" and TOS were largely matters of quality rather than commercial compromise. The characters were largely the same -- first-season Kirk was just Pike with a name change, McCoy was just Boyce with a name change, and Spock absorbed Number One's personality traits -- but they got more effective actors to play them. And in "The Cage," Roddenberry failed to deliver on his promise of a multiethnic cast, so it was at the network's insistence that the "change" of adding Sulu and Uhura was made. Plus it was Roddenberry's own decision to drop Number One altogether, rather than recasting her with a stronger actress like Lee Meriwether or Jeanne Bal as the network wanted, because it let him claim that the network was opposed to a female first officer rather than admit that they just didn't like him casting his mistress in the role. None of that is about "commercial interests," beyond the general principle that making a better show and appealing to diverse audiences will improve the chances of success. So I'm not sure what changes you're talking about.
"As Roddenberry intended" is not the perfect, superior thing that fan mythology would have it. A lot of what made Trek work came from people other than Roddenberry, people who improved on his ideas or pushed him to improve them. Yes, compromise is a part of the creative process, but so is collaboration. Other people's input can improve your work, and it's a poor creator who doesn't acknowledge that.
And when presented with the chance to 'restart' Star Trek, both with The Motion Picture and with The Next Generation, both times Roddenberry more or less leaned back on "The Cage" as a blueprint.
It's odd that you'd restate that belief when it's already been pretty thoroughly debunked in this thread. The "Cage"-like stylistic elements in TMP were more the result of Robert Wise's input, his preference for a cool, sterile future in the vein of
The Andromeda Strain, than Roddenberry's. We've covered this already.
And I don't see anything particularly "Cage"-like in TNG beyond the resurrection of the "Number One" epithet for the first officer. TNG was basically a reworking of
Phase II, with mature Kirk becoming Picard, Decker and Ilia becoming Riker and Troi, and Xon (crossed with Questor) becoming Data. Otherwise, the ideas Roddenberry contributed to TNG were shaped by his perception of himself as a visionary futurist, his desire to promote his utopian philosophy of a "Technology Unchained" future where humanity had acheived perfection and enlightenment and people lived solely to better themselves. That perception of himself as a philosopher rather than just a working producer was a belief he didn't develop until the '70s, when fandom started to see him that way and he bought into the ego-pleasing hype. The Roddenberry who created "The Cage" was just trying to make a successful TV show, albeit a smarter one than the norm for TV science fiction of the era.
Beyond that, TNG was largely the creation of David Gerrold and D.C. Fontana, with input from Bob Justman. Gerrold wrote the series bible and Fontana wrote the bulk of the pilot script, which means, by Writers' Guild rules, that they both should've gotten co-creator credit for TNG. Roddenberry fought tooth and nail to deny them their rightful credit by convincing the Writers' Guild that TNG was just a continuation of TOS. But they probably did more of the work of creating the show than he did. By that time, due to his advancing illness and drug addiction, he was barely even capable of functioning as a producer, and he had to be phased out to a figurehead role by the late first season.
It feels to me like GR wasn't always entirely happy with the way TOS developed following the second pilot episode, and was (either consciously or unconsciously) attempting to steer the franchise back to his ideal vision.
The idea that your "ideal vision" is what you started with and any change from it is for the worse is getting it completely backward. Any writer who thinks that way is an egomaniacal moron who's unlikely to produce any worthwhile work. The earliest form of your idea is usually its
worst version, because you haven't yet done the work to bring out its full potential and fix its problems. Creation is the result of a whole process of trial and error and refinement. There is no muse that drops a perfect, complete idea into your head at the start; what you begin with is rough and unformed and you have to work hard to make it better.
I think I read a while back that Roddenberry began considering the idea that became
Star Trek as early as 1960. It took him four years of working on the premise to develop it into something good enough to sell to a network. So obviously the need to keep working and improving wouldn't just stop there. No creation is ever perfect. There's always room to improve it. The goal of creativity is to move
forward to better ideas, to learn from experience and improve on your past work, not to cling fanatically to your unchanged ideas from the past. If you can't come up with anything better today than you were able to think of 25 years earlier, then you're in the wrong business.