I think at this point the lack of flying is just them fucking with us.
As far as embracing his destiny, I think this take on it is fair. I know a hundred people who left high school, muddled with a year or two of college, and didn't know what they were doing with their lives.
Clark sees himself as Clark Kent. It was a big jump for him to realize he could/should help people all over, not just his friends and neighbours. None of us would make that mental leap, and it's not just because we don't have powers, it's a psychological thing to see that your world extends beyond your own yard.
Superman doesn't exist. He needs a reason to create him, and while they are dancing around it now, there still really isn't one. Why should there be a Superman when the Blue Blur is totally effective?
The only reason is because the word of Superman would be trusted, and Clark has to get into situations where Clark Kent's opinion isn't worth shit, and people would listen to Superman. That also means he has to have the wisdom and maturity to have something to say that's worth listening to. He's still a guy in his early twenties at this point, and no one cares what he thinks.
Once this gets established, then there's a reason to have a person called Superman that people will actually call for help instead of saying "What are you doing here? This is a restricted area." Clark has almost enough reason for this now, especially with having to deal with police.
I don't think he had this in earlier seasons, just jousting with Lex all the time or knocking out some meteor freak. Now he is in a position where he has to present evidence against someone, and he has to show where the evidence came from, he needs an identity.