He always seemed bored. He would let Agassi — one of the best returners in tennis history — get three break points and then bomb four straight aces. He would have had to adapt his game some and tighten up the backhand, but I believe he would have.
I also wonder if Agassi wouldn't be even better today than he was in his era. He had a great all around offensive baseline game that would play even better today now that they have somewhat evened out the surfaces and balls used in the slams. He was a tennis savant.
I believe Agassi and Sampras belong with the Big 3 and that's it.