McDowell was the best thing about the movie. He's a great actor and his motivations for being the 'bad guy' were completely convincing (despite the Nexus itself being a pretty stupid plot device.)
You're right, McDowell was one of the best things about Generations. They had a great bad and nasty bad guy!
For me, Generations is a mixed bag. Generally, I found it underwhelming and slightly disappointing. I was really looking forward to the Kirk Picard team up and there wasn't enough of it and, as others have said, Kirk's death just didn't resonate. Both Ron Moore and Brannon Braga admitted that they failed with that and Moore also said Leonard Nimoy was right about their script, that it was weak.
It's just such a shame. It was a real missed opportunity, something that could have been so much better if Paramount and Berman had gotten Nimoy onboard earlier to direct. They could've had Kirk traveling to the future and had Nimoy, Bones, and Scotty there meet him.
Instead, Kirk is there at the beginning and end, both Nexus fantasies of the captains really don't work that well, and the Ent-D gets blown up by a BOP using a similar tactic, hacking Geordi's visor, that already occurred in TNG. Very contrived, just like the Nexus.
I was ok with the emotion chip subplot, although others thought Data was irritating, I guess.
I didn't mind that they killed Kirk off, it was just the manner of the whole thing and the whole story. It just didn't work well at all.
Good parts were the Picard and Kirk teamup. I'm a huge TOS fan and I love TNG too. I wanted more of that and I thought there was really good chemistry between the characters. Both Shatner and Stewart enjoyed it too and Stewart thought it was a shame as he would've liked to have done more with Shatner.
Maclolm McDowell, as said before.
The destruction of the TNG was spectacular, but it didn't resonate or hit me the way the destruction of the original Enterprise did in TSFS. That was a much bigger deal imo. At that time, it was hardly conceviable that they would do it. The Enterprise had been through so many near deaths and scrapes you just figured it would always be around.
Then they got the A in TVH and the D in TNG, so you knew at that point, that they would just get a new ship.
But, y'know, having said all that, GEN wasn't the only ST movie that left me feeling underwhelmed. TFF was more disappointing and Insurrection was just...pleasant.