This is what I like about Tim. A serious, but good-hearted and sometimes even playful kid, but emphasis on serious. He thinks too hard about things and sometimes takes everything too seriously. It's both a strength and a fault - and that's good for any character. This is the Tim I remember from Robin, and Young Justice.
And Steph is far too adorable for words. I think Steph's almost casual disregard for her own identity actually has to do with a lot of her character - there's none of this compartmentilization that dominates Bruce's mindset. The somewhat tragic thing is that I don't think Tim has the same issue either - I think that Bruce's M.O. has been so instilled into him that he believes he must separate his two identities. Not so much an issue for Tim, if he could ever shake his hero-awe for Bruce off.