It's really a fantastic Trek movie, a bit lesser mainly because it came in the shadow of Wrath of Khan, a classic of the genre.
It's also far deeper than it appears because while the Klingons are depicted as ruthless, in fact, they are absolutely justified in being terrified at the Genesis Device.
From their point of view, the Federation has developed a weapon of astonishing power that is dressed up as a terraforming device. The evidence they have is a video showing this "terraforming" device as a torpedo, and the first use of this device is the destruction of a nebula. If you were any other power in the galaxy, would you not see this as a Tsar Bomba level demonstration of force?
If North Korea developed a terraforming device that can convert a uninhabited thousand square feet of ocean into a garden, would you not be terrified? It doesn't require any known enemy to be terrifying.
Honestly, for a long time, I wished they hadn't made Kruge so apparently blood thirsty. After time I think it works perfectly. Put the shoes on the other foot and you easily have James Bond or James Kirk himself battling to defeat this weapon.
The movie itself... I think Robin Curtis does a great job but I think her lines made more sense coming out of Kirstie Alley. Curtis plays Saavik like a straight Vulcan and her judgments of David don't really make logical sense. Alley played the half Romulan thing so her emotional judgements made more sense.
