Probably trying to vary the posting time is the surest way to catch new visitors, and being aware if you have a target audience (I ship mostly to the US) of daily routines, as Marilyn1545 pointed out. I've got a logical range of times, based on time zones, for pre-work, lunch, evening visitors.
Google Analytics is helpful, but I realized that the peak viewing by hour that I was seeing was usually based on when I had relisted! So, take this GA information for what it is - we control the peaks, to some extent.
BTW, my views (and sales) are pretty flat, at the moment...