There's a distinct pattern to Star Trek movies:

Classic
-------
1-The Motion Picture: Awkward and rough
2-Wrath of Khan: Pretty good
3-Search for Spock: Disappointing
4-Voyage Home: Very good
5-Final Frontier: Truly horrible
6-Undiscovered Country: Awesome; wraps it up with a bang.

The TNG series isn't done yet:

1-Generations: Awkward and rough
2-First Contact: Very good
3-Insurrection: Disappointing
4-Nemesis: Pretty good
5-"The Search for Data": Truly horrible
6-"The Undiscovered Plot Device": Awesome; wrap it up with a bang.

They're not off the hook yet. The TNG crew owes us one really bad movie, followed by the excellent movie that allows them to retire honorably and the audience to let go of them. Your analysis of the way they laid the groundwork for the next two movies is absolutely correct. We'll see a "Search for Data" that sets a new low, and with that embarrassment out of the way, we can look forward to a magnum opus swan song for TNG.

--Robert