First of all I dont think Mishkin had an illustrious career at the FED. Few year down the line few will remember that he was even FED board remember. However many will remember him as a prominent economist. Your argument that his two year stint at NY Fed was illustrious lacks foundation compared to many other previous and current "illustrious" FED board members.

Regarding other economist I think the works of  Kydland and Prescott, Thomas Sargent, Robert Lucas, Rudy Manuelli, Ned Phelps, among others, shape the monetary policy work of the Federal reserve. Because of the cutting edge research of these "academic" people, the Federal reserve and othe central banks around the world benefit a lot.

Regarding Krugman, he won the Bates medal and he is due for Nobel prize few years down the line. I rank his works and advocacy higher than what Mishkin has done so far.