TWOK is really the first part of a trilogy. Taken as a whole, the TWOK/TSFS/TVH trilogy is bolder, grander, more dramatic, and ultimately more satisfying than most individual episodes of TOS.
I uh, strongly disagree. The Voyage Home is OK I guess but it isn't a patch
on episodes like The Tholian Web, The Cage, This Side of Paradise or Balance of Terror. I love Wrath of Khan but the following 2 movies are nothing special. I'd much rather watch The Motion Picture of Undiscovered Country, which resemble Star Trek a lot more.
It's a mess of a movie but I'm oddly fond of Insurrection. It tried to tell an actual science-fiction story unlike the following 2 knuckle-brained films.