I had the same problem. After years of Windows laptops, I bought a Macbook back in 2015 because I wanted a change. Ended up with the same problem. Tried all sorts of fixes. Reinstalled the OS several times. It would work for a day after the reinstall and then lock up after every sleep again. I guess it wasn't always a complete lock up. Once when I was beyond frustrated with it, I let it just sit. After 30 minutes, it came back on.

I returned it and went with a Thinkpad instead. On all my Windows laptops, sleep's never been a problem. Even on the cheap machines.