The only constant is change. (Which is why I don't get it when people freak out when the TARDIS changes, or the intro changes, etc. That's one of the many things I love about the show, is how much it changes yet still stays the same.
I do love Rory. He's just so laid back for a companion. He tends to just roll with whatever's happening around him. Or, at the very least, he shrugs it off as part of what goes on around the Doctor and Amy and keeps going.
He has notes to keep secret from his companions. "Suck it up and tell Rose you love her." "Donna only yells at you because she loves you." Don't let Jack hug anyone for longer than five seconds." <-- pinning for this note, too!