On the subject of selling insurance across state lines, there are no federal laws that would have to be changed since there are NO restrictions at the federal level. It's up to the states, not Washington, but then that's where the problem is, it's already been tried and the insurance companies wanted no part of it. The real irony is that the ONLY current insurance program that operates across ALL the state lines is Medicare, which is as close to a 'single payer' system that we have in America today. So if you think that delivering health insurance coverage across state lines is the solution, then lets start by allowing anyone and everyone to opt into Medicare, or what Bernie Sanders called Medicare Part 'E', where the 'E' stood for 'Everyone'. This would be what has been called a 'public option' which is what the Dems and Obama wanted right from the beginning. So the solution to all of this was there for the asking, but the Repubs killed it.
Some thoughts on the 'state line' issue:
http://www.nytimes.com/2015/09/01/upshot/the-problem-with-gop-plans-to-sell-health-insurance-across-state-lines.html