As far as at the national level, I would like to see it set to $15 nationally and tied to inflation but phased in over the course of about 10 years or so so the companies finally hit that point but slow enough that they aren't hit by a huge shock. Then possibly having a state level minimum wage for the places where it honestly costs beyond that to achieve the same standard of living.
I personally see $15 an hour as totally doable by the current systems after adjusting prices and maybe profit margins some. With the long term benefit of a stronger minimum wage being increasing purchasing power for both the lower and middle class which will spur the economy and increase demand as a whole which is actually is the true job creator in the US and will actually allow many more to open up their own companies if they wished.
The sad thing about paying their fair share when it comes to companies:
if none of them do it, everyone suffers in the long run,
if all of them do it, everyone benefits in the long run,
but if everyone does it but one person, everyone benefits some, but they benefit more.
And if no one does it but one person, everyone still suffers with that company suffering more.
So without laws forcing this stuff, most never will do it unless they have the pull to do it and pull it off.