if humans didn't have to sleep...

I'll think about it and probably yes we will be lazier. But just to let you know, in this life, I am often a SLEEP ADDICT and I had many moments when I felt like sleeping during the day etc to escape some or other kind of life's err troubles or uncertainties.

I wouldn't recommend it very much.

There's so many things I'm interested in and want to do. I would get much more done.

Different races would react differently to this. White people would do well, others may struggle with extra time, falling into crime and violence.