Forgive my ignorance, as I haven't seen the Director's cut in five years, so my memory is a bit fuzzy, but, having now watched the original, I honestly didn't find much difference with the pacing. If anything, the original seemed faster paced, as the Director's Cut made the overture even longer, and the original is lacking Ilia's random magical Chekov healing powers. Also, I liked the original effects of the crew walking to V'Ger as opposed to the pixie dust bridge the Director's Version added. But like I said, my memory of it is not good enough to make that judgment. I just remember watching the Director's Version and thinking, "Geez, they say the pacing here is much better than the original cut. How would I ever make it through that?" But it certainly didn't seem any worse to me.
Okay, so now I've watched this movie twice in two days, the second time with commentary, and I am now ready to deliver my full opinions. Well, to be honest, they're not much different from the thoughts I gave earlier when I was halfway through the film.
As I already said, I have enjoyed my time with this film, more so than I ever have before. It is a beautiful film, and I appreciate it even more now that I know I'm seeing what was accomplished in the late 1970s and not having to wonder if this was something made decades later with the Director's Edition. I would contend that no Star Trek film since has matched the impressive visuals of this film. There are a few effects that don't hold up, but for the most part, there is a level of detail and majesty that looks perfect even today.
Also, as I said before, the amount of detail in regards to ship functions and ship locations is second to none in this movie. I love getting to see the sonic showers and the rec room and the sickbay and all of its readouts, the thruster suit and all of its controls, the fact that the chair heads move up and down and the arm rests fold in for protection. It's a nerd dream come true. You really don't get to know the ship as well in the future films.
There is a really nice tone to this film. It feels so different from any of the others.
That said, I still believe all of the above is definitely at the expense of telling a story and that the piecemeal way in which this was constructed definitely shows. In many ways, it seems they were more interested in showing cool things than having a story happened. Two of the most interesting and engaging sequences in the film are, in my opinion, the transporter accident and the wormhole journey. However, neither of them have anything to do with the story (well, the former is a bit of an excuse to get Spock in the picture, but he was already on his way long before Sonak got turned into goo). And it just seems they're there because they're things they couldn't have done on the television series. That incredibly self-indulgent feeling permeates this film. "We've never seen the Enterprise from 147 different angles. Let's do that! We've never seen someone killed by the transporter. Let's do that! We've never seen Kirk dressed like he's going to play tennis. Let's put him in that for half the movie!" Okay, that last one is obviously a jab at their terrible uniforms in this movie, but you get my point.
Up until the last 40-45 minutes, this movie feels incredibly padded (mostly by shots of the characters looking at stuff), because I just don't think there's enough story here to fill out 2 hours. What story there is is very interesting, and it really does start to get good in that last stretch. But all of that cool nerd stuff I mentioned earlier really seems to be there to distract you from the fact that the story's not going anywhere.
Finally, as for the characters, I do enjoy Spock's journey, and I give it a little more credit than Nimoy himself did (then again, Nimoy gave his approval to the Abrams films, so what does he know? ;-) ). And, as I've already said, I enjoy the rivalry between Kirk and Decker, and Kirk is presented as an interesting, flawed person. However, that's really only resolved by Decker disappearing, which is rather disappointing. And while I like Decker, his decision at the end seems almost completely unmotivated. He never expressed any kind of desire to reach a higher level of consciousness or make sweet, sweet love to a computer. And it's in that moment that I realized I didn't really know Decker well enough to know what the hell it is he wants. Well, the best I can come up with is, "Shit. This is the worst day ever! I lost my ship. I got demoted. My girlfriend got killed and replaced with a robot. Fuck this. I'm going to become a god and cast down my vengeful wrath on all you assholes!" But from a production standpoint, it very much reeks of giving the film a personal cost but only by doing away with the expendable characters. As for the rest of the cast... they're there.
To sum up, I can definitely understand why Jimmy Doohan fell asleep during the premiere. This is one of the best examples of proving that a film can't stand up with just special effects, and there is a ridiculously high level of special effects. They suffocate this film. The plot meanders, and we're expected to be impressed because the movie looks impressive. But it just needed more story. But I did find it enjoyable, more so than I ever have before, and I'm glad to finally have it in my collection. Thank you, Walmart, for packaging these two movies together so that I could pick up these original versions up without having to buy all the other movies that I already own.