Everything that wasn't a part of the mindlessly inane main "plot" was really good. Visually it was fantastic, the score was wonderful, and there were some great character interactions and a good sense in general that the crew was close. The design of the Valdore is another thing that I personally love.
It's just such a tragedy that all these wonderful elements go so horribly to waste. If only the Romulan movie had actually been about Romulans.