if someone is 3betting light constantly with high 3bet numbers and I have position on them, then i'd 4bet with AA-JJ, AQs+, AKo, maybe down do KQs. Anyone that is a habitual 3bettor you have to be careful about 4betting to light as even though they 3bet an absurd amount, they can and will have it sometimes and you don't want to be 4betting him light the times that he does have it. Also check his fold to 4bet stats and see if he is 3bet folding to a 4bet a lot and make your range decision based off that