Sleep is important, but is only 1 aspect of a big picture. If 2 extra hours is going to hinder other important factors, then don't bother. Just keep your sleep patterns regular, do what feels natural/right and focus on everything else. I doubt you would see much of a difference between 6 hours and 8 hours(in respect to muscle gain/fat loss).
It's more about a healthy balance, lifestyle changes and consistency IMO.