That was Gene Roddenberry's influence. He insisted on things like that. This is hard to say, but after he died is when the series started getting better stories

A lot of the first two seasons were recycled "Star Trek- Phase II" scripts from the late 70's.
those are the uniforms Sulu should have been wearing.
(or should i say Thulu (said with a lisp) )
and Star Trek: The Next Generation (TNG) trivia
the star dates mentioned in TNG actually have meaning.
They all start at 4XXXX ... the 2nd digit is season and the next
3 numbers indicate the location of the season
so 41233 would be season 1 near the start... and 44789 is season 4
near the end...and so on
and LOL at the darmok references.
some of my fav episodes were
Yesterdays Enterprise
I, Borg 1&2
the one with the tribbles where they went back in time to the old Enterprise(with Kirk)
The one where they found Scotty (trapped in a transport buffer) LoL when he was talking
to Geordie. When Geordie tells Picard how long it will take to repair. and Scotty says how long will it really take? 2hrs.. oh you didnt tell him how long it will really take
I liked the one with Worfs girlfriend - where they meet the Klingon ship (that were in hibernation sleep and about to wake up after 80 so years)
Any episode with Majel Barrett (Troi mother) is an instant turn the channel.