Amend Obamacare to consider low-income families who get good health insurance through work

Currently there is a planned luxury tax for health insurance costing over a certain amount. The specific example I was recently made aware of has that luxury tax at 40%. A person working, earning a salary of ~$16k per year, currently pays 7% of the cost of their ~$28k insurance, not a lot to pay for high quality health insurance. Once 2016 and the 40% luxury tax hits, this person would be paying ~33% of their income for health insurance. I feel this is a drastic oversight, because a person earning $16k/yr simply cannot afford to pay a third of their income to health insurance. As a fix, I would suggest a blanket waiver to that luxury tax for all those whose income is under a certain amount, as a number I would throw out $40k/yr.