IMO their psychopathy is identical. Both are full of hidden rage. Both are master manipulators and liars. Both are narcissists.
TB's girlfriend disappeared after she rejected him. Nobody knows if he tried to find her to kill her or not. That is a distinct possibility. In those days there was no internet, no cell phones, no IMs, email. All he had was his used VW in which he drove all of the U.S. It obviously would not have been as easy for him to locate that ex-girlfriend then as it would be now.
Both TB and JA want to "own" their victims.
Whether JA got her sexual thrills from butchering Travis or not is irrelevant. Her deep rooted rage was satiated, as was TB's after each of his murders.