As I understand it one one of the reasons given for not canning the ACA is that no one has as of yet been harmed by it, once the first people have had to to pay a fine will it go back for review?
That wasn't really an issue with the decision that was made. It could have been a threshold issue - a reason why parties didn't have standing to challenge the mandate yet. But to the extent it was, that standing issue was overcome and courts, including the Supreme Court, considered the issue on its merits.
That said, in theory its possible that there could be new as-applied challenges to the individual mandate that would be decided by the Supreme Court. I suppose its even possible that there could be other facial challenges to it - i.e., ones that didn't depend on it being applied (and actually causing harm to particular entities) or didn't challenge how it was being applied. Someone could, e.g., claim that it violates substantive rights protected by the Constitution or that it violates equal protection guarantees. In NFIB v Sebelius, the Supreme Court didn't say that the individual mandate was definitively constitutional - that it comports with the Constitution in every way necessary. What the Supreme Court said is that it doesn't fail for want of constitutional authority to enact it - i.e., it is within the scope of Congress' enumerated powers, specifically the taxing power. Even if something is within the enumerated powers of Congress (e.g. the Commerce Clause), it can be found to be unconstitutional because it violates other provisions of the Constitution (e.g. the Second Amendment). The Supreme Court hasn't considered challenges to the individual mandate based on arguments that it violates various other provisions of the Constitution. I wouldn't hold out a lot of hope that such other potential challenges will be successful though.
But that all relates only to the individual mandate. There are lots of other aspects of ObamaCare, or its implementation, that have been or might be challenged in court. The extension of premium subsidies to coverage bought through the federal exchange is one such aspect. We might also see challenges to the Administration's decision to delay enforcement of the employer mandates. There are already petitions before the Supreme Court relating to the requirement that employer-sponsored plans cover contraception. We should know fairly soon whether the Court will hear one or more of those cases. I suspect it will, lower federal courts are already divided on the issue so it would seem to need to do something there.