HealthCare.gov’s new EZ application for coverage can’t be used by legal immigrants or naturalized U.S. citizens, prompting concern that many Hispanics and Asians will go right back into long enrollment queues this year. The Obama administration has placed a high priority on signing up more Latinos under the health care law for 2015. As the nation’s largest minority group, Hispanics tend to be younger and more likely to be uninsured. An administration official says there have been significant improvements in the application process for immigrants, and more are expected in the future. But advocates are unimpressed. “The whole idea was...