Crowley had to say, Michael was a great deal different than any of his brothers. He wasn't sure how much difference he was seeing because of the cage's influence, but it was certainly noticeable. Raphael was quiet, methodical, almost clinical in his methods. Gabriel was all over the place, a literal mixed bag, though underneath all the Tricksterness Crowley could see there was the righteous angel underneath all that candy coated snark. Lucifer was, well. Lucifer. There wasn't really any need to elaborate from that. But Michael, he certainly fit the older brother role.
Raphael might have been unflappable in the brief time Crowley had known him before Godstiel blew him to smithereens (and did Michael know about that yet?) but Michael, there was a subtle difference with him. He might not as much as cracked a proper smile since Crowley had seen him (and Crowley was quietly making it a mission to make him smile at least for the fraction of a second) but he had a sense of humour, something which he was sure Raphael most likely didn't.
"No need," Crowley shook his head. "The one that left the biggest impression on me was Lucifer, and I'm pretty sure you know how that goes," he didn't want to touch on a potentially touchy subject between the pregenitors to Cain and Abel so he moved on from that smoothly. "I only knew Raphael briefly, and he was all business, which I can admire, really." And of course, Gabriel was the new friend, the wild card.