Re: Khan the most dangerous enemy of the original crew?
The Enterprise also encountered multiple near-omnipotent beings in the original run of the show. Khan was hardly their most dangerous enemy... but he was probably the most interesting human-scale threat they faced.
I wonder if there's a deleted scene from Space Seed where, unlike with cosmic beings and soulless androids, Kirk's plan to seduce Khan somehow failed.
"A life is like a garden. Perfect moments can be had, but not preserved, except in memory. LLAP" -- Leonard Nimoy