Roddick, for sure. Unfortunately, he is also among the dumbest.
At his best he had two of the biggest weapons in the world. He sought out more consistency. And when he got too passive he looked to be more complete. Somewhere along the way, he lost the plot.
Obviously a lot of that rests on his bouts with Federer. I don't even know why people bother bringing up Nadal etc. It was really just that guy.
Nonetheless, he was a big name on hard and grass, a contender at two of the four Majors, variously, deceptively consistent at the AO, and just in case you couldn't stand seeing so much of him, he did you a favor by taking a few months off during the clay season.
I'd probably go with Ivanisevic after that. The Muster mentions must be a preferential thing.