The King used to be good back before he started playing some kind of tweener, when he was straight heel.
Lawler was good, but he used a lot of stock lines that have been used before.
Most of his material was not original.
Heenan thought up a lot of funny things to say on the spot, and they were often contextual rather than generic.
But I agree with you that "The King" was very entertaining in the late 90's early 00's. Good chemistry with JR.
Realised how good he was when Heyman & Coach replaced him for a time when he quit the company.