What would inline mean: He shouldn't be lvl 16, because of 10% XP malus due to violation of multiclassing rules.
Human = highest class does not count; all other classes shouldn't be more than one level apart.
With your combo he'd have the 10%malus for at least three level ups, which IMHO forbids a total of 16 levels.
I think more of 8/4/4 or 8/4/3.
You know, Nale's "optimized" :D