TOS is the only true visionary Trek. The others including TNG are extrapolations of that singular unique vision and more an amalgemem of many different visions and takes on the same subject material. Only GR was able to harness and focus the efforts of the geniuses of the day into a collective gestalt. The others were like the bands that followed the Beatles and the child actors that followed Shirley Temple, etc. or the radio piece that follows Beethoven's ninth symphony. Certainly not an envious place to be but Brahms did it, etc. so it can be done, if you're Brahms.