Obamacare is going to save my life, and for that I will always be thankful to Obama... if it gets repealed in the next year, chances are I won't get to be angry because I'll [barring some miracle] be dead. (My backup plan as of right now is to beg Oprah for money) So there's that. It's a bulky, terrible piece of legislation, but it is the best that he could get passed, and I knew a lot of people who would be alive today if it had been passed 10-20 years ago. The United States healthcare system is broken and it has been for a long time, the real issue with Obamacare is we need an overhaul, not a bandaid.
Obama isn't a terrible president; he's just as bad as all of the other presidents. The indefinite detention bill, for example, is a nightmare, but would've been passed by Bush or pretty much any previous president. The situation with Edward Snowden was badly handled. The Benghazi scandal... appears to be a hoax, actually. A lot of media circus with little to no substance.
The biggest thing I've noticed in the last couple of years is Obama's hands being tied by a Republican-controlled congress. Frankly, I've been shocked and appalled by their willingness to put American lives (both literal and financial) in harms way to obtain their political goals.
So for me it's a mixed bag. I'm impressed by his idealism, but not by some of the specifics of how he handled his job.