Roddenberry's strength was his world building and tone setting. Like a general should have left the lesser affairs to junior officers. Either that or he stepped down and allowed himself to be directed.
Even saying that, nothing is mentioned of the influence of everyone else that were as crucial to Star Trek as he was. I keep seeing it mentioned how big the influence of Gene Coon was, but I haven't see anything from SF Debris or anyone else that directly goes into such the subject. All that's usually said is the heart of Trek, especially its characters personalities, were the result of Coon's influence as well as the emphasis on flawed, yet striving humanity.
I'd like to see that looked into with a bit of detail, because from what I know of Roddenberry's time writing for Have Gun Will Travel, those things are exactly what he did. You can watch those episodes he wrote and feel how similar they are to Trek based solely upon the witty banter and the interplay of idealism and flawed yet striving character building that TOS was famous for.
Examples for anyone willing to peek:
https://www.youtube.com/watch?v=RpVTkbblsYw
https://www.youtube.com/watch?v=kYNevucT52U