He came in and did what he could. It's felt like his hands have been incredibly tied most of the time, though I wouldn't want to give Republicans the sort of unfettered control that I wish Obama had, so there's that.
I do wish he'd have been more willing to full-on confront the BS he was faced with in the beginning and call out the detractors. I think he'd have done more for his race to politically sacrifice a second term to say, "okay, here's my birth certificate, the christmas tree in the residence, and by the way, I stole the idea for the ACA from Republicans--it reduces freeloaders, you idiots." And I say "it'd do more for his race" because I do believe the blind resistance to cooperating with him was based solely on the color of his skin and the fact that his last name sounded like Osama and his middle name was that of a former dirtbag middle eastern ruler.
I think his ideas were great, but in the end of the day, he needed to do more to defend himself and his policies. He was too silent and never tried to control the message.