After rescuing Obamacare from a potentially crippling legal challenge on the applicability of subsidies to consumers who bought their insurance from federal exchanges, the high court still has some major judgments it needs to decide on. Here are some of the crucial matters still on its plate:  
“Violent felonies” and armed career criminals
Deciding on the challenge that the definition of a “violent felony” under the Armed Career Criminal Act is too vague, could be momentous, especially for minor repeat offenders who are locked up for years based on loose interpretations of the law. 

Costs of cleaning up emissions
The court is being asked to have the Environmental Protection Agency consider the costs of lowering emissions before framing regulations, by a large group made up of states and major industrial entities. The government has countered, saying the law doesn't refer to costs when requiring agencies to adopt appropriate rules regarding emissions. The decision on this matter might significantly influence the framing and implementation of environmental laws in the future.

Same-sex marriage
Deciding on the constitutional validity of prohibiting same-sex marriages and whether states can refuse to recognize such marriages in other states could effectively put a stop to the drawn out legal wrangling over the years on the whole same-sex marriage issue.

Keep tabs on the court's pronouncements on these matters, as they might well have an impact across the country.