While I liked Nemesis and thought it was a decent enough movie, I have to admit that part disappointed me a bit. It was the first Star Trek movie to really feature the Romulans in a primary role (

for it taking until the 10th movie to finally do that, BTW). But it would have been nice if they were the primary villain (or even a faction of Romulans if they wanted to retain the part about Donatra's forces joining the fight). While their role was undoubtedly the biggest in Nemesis up to that point, I wish it had been more.
The final battle scene in the last part of the film is one of the best of all the films IMO. That collision scene still gives me chills and the sound effects were intense for that. And while I wasn't a huge fan of the clone idea, I did like Tom Hardy as Schinzon.