The light front end feel at high speeds may be due to rear tires being worn far more than the fronts. Although it sounds like a small amount, aerodynamics are very sensitive and the stock NSX is typically dead level on new tires. (At least mine was and I've seen many others that looked slightly high in the front with worn tires.)
Also, since the rear caries more weight, it may be that over time the rear springs and shocks sag a bit more than the front. Again, it doesn't take much at those speeds especially with a mid engine and otherwise aerodynamic design.
Also, since the rear caries more weight, it may be that over time the rear springs and shocks sag a bit more than the front. Again, it doesn't take much at those speeds especially with a mid engine and otherwise aerodynamic design.