The problem, as I see it, is that if a "mere" assasin is going to have a score of nearly 40 in int, how much more the "wizardly" scions are going to have?
Beyond that, the stats appear to be reasonable.
And there is no reason why an assassin and wizard can't be comparable in Int scores - one doesn't have to be better than the other. heck, a wizard that takes assassin levels would be one deadly SoB...