Out of all the Johto starters, my only favorite is Cyndaquil. Not Quilava, not Typhlosion. Just Cyndaquil. And that's because it can 'sheathe' his its flame quils. Also, it's not a dumb flame mohawk or a flame mane or a flame BUTT. Yuck.
They're all able to "sheathe" their flames as you put it. In fact, the Gen VI animations have them put away when not attacking.
I like the line as a whole, but I've always preferred Quilava to Typhlosion design-wise.