Brubaker is a freaking genius. That is right I said it..a freaking genius. What he has been able to do with Barnes as Captain America is just top shelf story telling.
Barnes wants so much to prove that he deserves to be Captain America that his impending trail (while it is going to be a circus) is his cross to carry.
This twisted game set in motion by Barron Zemo is about to get even more horrid as the new Red Skull (the daughter of the original) has been set free from her own personal incarceration and has only vengeance on her mind.
You can say what you want but under Brubaker's guidance Barnes has more than proven that he wants and deserves the responsibility of being Captain America. He is a changed man and that is in part due to not wanting to let Steve down and his growth as a person. He still has moments of doubt but there is one thing that is certain. Being Captain America is everything to him.