Time to revive this thread with one more mismatch. I'll look through the entire thread and add links to specific matchup analysis in the OP soon.
Murray vs Simon
Murray vs Murray light? Everything Simon does, Murray does better - he's pretty much a fitter, stronger and more athletic version of Simon. You almost feel that he can routine Simon without really getting out of second gear. This is arguably one of the very worst mismatches in tennis: in a matchup like say Berdych vs Nadal, if Tomas redlines his game and plays his best he can definitely win, if Simon plays his very best against Murray odds are he's still losing in quite straightforward fashion. He doesn't have any weapons to hit through Murray and while he's consistent off the baseline, Murray is even more so.
Two more that seem interesting....
Hewitt/Karlovic. Karlovic leads the H2H despite being basically all-serve, and Hewitt had one of the best return games on the tour, matching up very well with other S&V players.
Federer/Murray. Particularly given Fed usually owns Muzza at Slams.
Karlovic's serve is not your traditional big serve, it's the best there ever was. Some players could get a decentish read on it, Hewitt wasn't one of them, he couldn't cope with the combination of power and angles.
Federer vs Murray is an interesting one. When Federer is really on his game, Murray pretty much has no chance as he doesn't have the tools to take the initiative off Federer. But when Federer is even a bit off ie prone to shank every third backhand, Murray has the ideal skillset to frustrate him ie he can attack his second serves and defend him into oblivion provoking shanks and mishits, etc... Post-2007 Federer was rarely at his best for non-Slams/WTF, which explains the H2H. Even at their respective ages, I'd still expect Federer to win most of their Slam meetings, although his decreased recovery powers might throw a spanner in the works (ie if he plays a five setter before facing Murray his task will be much harder).