Cousy is a terrible example, unlike most guards of the time he would use the left hand very heavily. Also could finish with both. IIRC, he was ambidextrous because he broke his right wrist or arm when he was in high-school and played a season with a cast on. Watch those famous final seconds of the 1972 finals and see how comfortable Cousy was dribbling with his off-hand. When it was necessary he would do it. Dribbling was just different those days, different rules, different role in the game.
Robert Williams is always spaced out. Reminds of Patrick O'Bryant. Hasn't looked like a good prospect so far.