Lee and Amare would be a terrible defensive fit - and a bad offensive one too. Amare is a pretty competent center - yes there are matchup problems at times, but the matchup problems are double-sided (that's sort of what they count on). But Lee and Amare dive to the bucket - the only way the offense works is if Amare is playing the high spot which is a waste of his versatility.
For Boston, Lee is a terrible fit because he is a horrendous defender. Now to expect Perk level post defense is a fool's errand, but he can't even try. And on offense he provides few complementary skills. I'd rather sign Shaq for the midlevel for that.