Obvious intelligence (especially in the eyes), dark hair, British accent a plus (or any other one from the UK), smiles easily. Like 'em tall, too. Good shoulders.
(BTW - all of this is in my personal romance novel in the form of a hypno-therapist I created for my leading lady. I write my ideals into existence so I can have them at some point in my life instead of waiting for them to never show up.)
(It's a sadness, isn't it?)