Listen I agree with people who call JJ an opportunist, because they do so on the basis of JJ playing market games and working backward from them. Gene was an opportunist to some degree too, but it cannot be said that he worked backward from marketability to story and characterization. The pilot episode of the cage was how he originally intended Star Trek, with women wearing pants (female first officer) and a generally very cerebral vision (admitted so by both Gene and Majel in interviews, and they should know, if anybody should, right?).
Gene was forced to make concessions, like putting women in skirts, changing the first officer, making the bridge of the enterprise more colorful, etc.
But it cannot be said that he worked the same way that a JJ abrams did, from market value backward. Someone like JJ basically says 'okay so what attracts people to theaters? Oh yea, colorful explosions, people dissing each other constantly and smart mouthed women who make incest jokes haha'.
Gene make Star Trek Marketable to a fringe movement, and the films to a more universal movement, without compromising what HE wanted the characters to be like. JJ approached his 'version' of Star Trek from the immediate standpoint of compromise. He knew what general audiences liked and delivered based on his knowledge of that. Whereas Gene took opportunistic liberties by fitting his vision into a somewhat universally translatable vision.
JJ just saw dollar signs...(which is not to say Gene didn't want money either, but he didn't completely and utterly dumb down the medium for it)