The Only Republican candidate who can expect to be in the running for the nomination who will not get high negatives from the MSM drones is Romney. So, based on your analysis (i.e., that high negatives will mean we can't choose that candidate) then Romney is your guy.
There is no chance of the media creating the kind of negatives about Perry that they have about Palin. He is as qualified as any candidate could be for the job of President with over 10 years of executive experience. The economic record he can run on is unmatched by any candidate. He didn't quit as governor and make millions in the process. They don't have three years of gaffes to turn him into Dan Quayle.