In regard to his overt and explicit attempts at legislation, he's too far to the right in basically every policy category. As far as his rhetoric goes, I'd like him to be further to the left on race issues (he's spends too much time toeing the line to placate the unreachable white social right).
I think that being black, that could be counterproductive. As mild as he's been on the issue of race, you still have Glen Beck saying that he has a "deep-seated hatred of white people," Rush Limbaugh calling the ACA a form of slave reparations, etc. You had huge outrage over his extremely mild and even-handed comments on Trayvon Martin (basically, saying he empathizes with the family and the killing would be investigated).
The rhetoric I would criticize was going along with ridiculous comments about the need for "belt-tightening" and comparison of the federal gov't to a household. And that was around the time of the sequestration cuts, which I very strongly disagreed with (and said so at the time). I thought that he could have stood his ground on the debt ceiling back then (as he later did) and won, and avoided the cuts. Further, if he didn't agree and had to give in, he didn't have to present it as a positive move.
No one on the political left likes Obamacare. At best, it is viewed as a necessary transitional program to single-payer. I don't think I've EVER heard a Democrat say it's the "greatest thing since sliced bread". JVS has cited it as stifling the growth of costs better than had been expected while still accommodating many previous uninsured. That's about as high of praise as I've seen. Also, worse option of the 2.
I think that given the constraints in place, it was as good as could have been hoped for, and I don't just mean Congress. We had a situation where most people were pretty happy with their personal level of insurance and where there was a massive infrastructure in place to provide it. and on the other hand, a lot of people could not afford insurance (either because they had very low incomes or because for their particular situation made it extremely expensive), and costs were rising at an unsustainable rate. So the challenge was to A) help people who can't get insurance to get it, B) keep cost growth down, C) (what a lot of leftists miss, IMO) not blow up the system for people who are happy with it. The ACA did about as good a job as can be expected of hitting all three goals (better than I would have expected, and I supported it at the time).
To me, the controversy over who gets the credit is mostly a non-issue (though it's funny pointing out to Republicans who call it the worst thing since sliced zucchini that it was similar to what Republicans supported not too long ago) because once you really think about it, the options were pretty limited. If you want people with pre-existing conditions (those with "particular situation(s)" that I said made it extremely expensive to get care) to be able to get coverage, you're pretty much forced into a mandate (otherwise, people will just wait to get sick until buying coverage) and then you're forced into subsidies for people who can't afford it.
The details can vary, but the combination of mandates, subsidies, and community ratings for people on the individual market are going to be what you land on no matter what your ideology or perspective is if you're trying to solve the problem of not enough people having coverage. Single-payer is essentially the same (instead of a mandate to buy coverage, you just give it to everyone and charge them for it and progressivity of taxes substitutes for progressivity of benefits), but it has the problem of what to do about the existing industry and the fact that most people are happy with their personal coverage. And then you throw in cost-cutting measures on top (ones that have been proven to work and a much more than are experimental).
I think if you're starting from scratch, you'd rather have single payer or even National Health, but given our actual starting position, it wasn't happening. Further, I don't think that single payer is coming any time soon. The way I can see it coming about would be a public option combined with a move away from employer-provided care so almost everyone's buying on the individual (community-rated) market and the public option is outcompeting private insurers. But I don't see that happening soon, if ever.