I get the impression that Generations was a result of studio interference. The TV series operated on its own, with the producers and writers doing just fine in guiding the direction of the show. But once it became a feature film, there was a lot of money involved and it was now under the jurisdiction of the movie department. Studio execs often don't trust filmmakers, especially ones from TV. That said, too much of it felt like it was written as a TV episode rather than as a film.
The opening sequence with the Enterprise B was excellent. It had a tone and feel like the previous movies, and really gave Kirk a heroic sendoff. Once the movie jumps into the TNG era, suddenly it felt like a widescreen TV show. I hated the slow-motion shots of Worf and Crusher falling overboard into the ocean (and later slow-mo during the action scenes). I also objected to Picard's brother and nephew dying in a fire. That was unnecessary and cruel, especially considering how they were portrayed in the episode "Family." It gave a very somber and uneasy overtone to the rest of the movie. I actually liked Data's use of the emotion chip because it was the next step in his evolution as a character. The treatment of some of the supporting characters (especially Crusher) was as bad as in the original series films. The rest of the plot was fun, but once we went into the Nexus, things fell apart. It was a concept that wasn't thought-out very well and created far too many questions than it answered. For instance, is Kirk still in the Nexus in some form? Of course, the entire ending fight was totally unnecessary because if Kirk and Picard could go anytime anywhere, they could have come up with a much better plan than to just engage in a fist fight on the side of a mountain with Soran. Once we realize what exactly the Nexus is (or at least what we think it is, since it's still rather vague), it makes Soran's goal nonsensical. And yes, Kirk's actual death doesn't do him justice. The entire third act should have been re-written. In fact, it's hard to believe the same people who wrote this film also wrote the amazing final episode of the series.
Overall, the movie itself is not bad, but it could have been so much better since there are a lot of problems with it. It can be enjoyed if you don't think about the plot holes and how they handled the characters.