Barrett winning, the Nexus angle and subsequent Cena/Orton feuds were great and something new at the time. Barrett didn't have to win the title match. If they made him go after the United States Championship during the Nexus angle it would have ruined the momentum of the stable. Barrett jumping straight to the WWE Championship match made more sense at the time. However, if Bryan had won (Nexus could still have formed) and used his NXT win to get his United States Championship shot against Miz, there would have been nothing wrong with that.
With that being said, the first two seasons of NXT got it right. The winner received a title match on PPV. What ruined it is not NXT Redemption. What ruined it was a combination of two things. They did a divas only season. How can they seriously expect anyone to remain interested in that for longer than two weeks? By the fourth season no one cared anymore. Secondly, the winners of seasons 3 or 4 never got their title shots. Heck, the fourth NXT winner barely even got a push, let alone his tag team title shot with R-Truth. WWE should not make promises they cannot keep. One could even argue that they blew it with Kaval too. He received no angles beyond his PPV match.
So, yes, guys like Daniel Bryan are who should come out of NXT as strong names to give title shots and potential pushes to. That's what NXT should have been. Not a divas only "experiment" that no one cared about, or having a winner never receive their title shot. I won't even start on NXT Redemption. That show has absolutely nothing to justify its existence. It is a waste of time for everyone involved. If they had just stuck with the original format of NXT and given the winners their pushes then the show would still be around with people watching it, rather than NXT Redemption online that even the 4 people who watch it likely dislike.