I find the blade on my Gravitator to be quite good at a lot of tasks, particularly anything involving the point. In fact, it may well be the knife that I have on me most often (albeit as a secondary blade) because the straight blade is no slouch, and it's got one of the best designs out there for point work (that swedge on the blade just after the thumb ramp makes for a great place to put your index finger in controlled tip work).
That being said, there are times when I've felt like that straight blade just gets in the way and have wished for something curved. If most of his cutting is with the tip, I'd probably say not to worry about it, otherwise a one-and-only knife to get for general utility should be something with a little belly.
I've never handled the Nakamura, but I would still recommend to show him the Benchmade Resistor. Its styling is very much like that of the Gravitator, but its blade is much better suited for general use.