I love this episode, it’s a solid 10 for me. As far as I’m concerned, Shatner’s performance sold the series. The entire episode stands or falls on the leading man here since he carries the emotional and dramatic burden. It’s Kirk’s story, how he deals with this threat, how it affects his oldest friend and how his decisions will save his crew. It is the template for the series to come, only with extremely little humor.
Solid summary. WHMHGB is not just a fantastic TOS episode (one of the best ever produced among all ST series), but grand television.
Historically, pilot episodes tend to hammer too many concepts, trying to sell the merits, the "you need to watch this, because--"
elements, leaving a raw, stuffed product that--if lucky--reveals potential, but in the end, the episode seems to be its own animal compared to what will follow.
WHNMHGB does not suffer from that, as so much of what made Star Trek "that show"
came to life in the episode, and guided the rest of the series. It is no coincidence the title is the end-call to action of the series's title narration--going where none have gone before is Mitchell's story--and that of Kirk's Enterprise.
We cannot know a history that never happened, but I seriously doubt any of the other stories considered for the 2nd pilot would have had the power and influence of WNMHGB.
Rating: 10...and beyond.