Just the idea of combining DS9's crew and ship, with the TNG's crew and ship would have been a great movie idea, even if they didn't focus on space battles.
One of the reasons why I think that, is that because the last to TNG movies were not as popular or successful, yet DS9 had a storyline that could have provided a lot of good material and plots for a movie.
With Insurrection, it had a more crew based and "human" storyline, and with Nemesis, they had more space battles, so both approaches were attempted.
I actually liked the first TNG movie, the plot, character interaction and all.
Worf was part of DS9, but they always made sure to bring him back somehow, in each of the TNG movies, which when you look at it, seems kind of odd.
Not only that, but he somehow always end up taking his former tactical station.
Why Worf would be in Insurrection during the Dominon war, when he is the station's strategic operations officer, seems kind of strange.
So it seems like they insisted on following the classic formula of having all the old gang together all the way to the last TNG movie.
Why not just combine crews and with the popular Dominion War storyline which would credit both casts?