Maybe Richard Helms, the famous CIA guy? AFAIK, Reagan held him in high regard. He was a bureaucrat of well known efficiency and an ardent anticommunist.
If not Helms, why not Jeanne Kirkpatrick? Reagan was a big proponent of hers, after all. She was not very popular with many people outside the administration, with the exception of the people she advocated for propping up, but you never know.
If Reagan wanted to go more practical and less ideological, he could go with Scoop Jackson in the spirit of bipartisanship. They were similar on foreign policy, after all.
But basically, I think Reagan if he goes ideological will do so in a way to piss off his opponents. Its kind of like how we now have Lamar Smith head up the Science Committee in the House; its a slap in the face to the Liberal establishment more than anything.