If it was only subjective time I don't have as much of a problem with it as I would if it was actually universe wide,which not only would also mess with Ybris creating the idea of procreation but would mean completely intruding in the domain of another god

 As for having nothing to do I don't believe that, Artis could for example mess with time and space/sun to create the seasons (time for the obvious, space/sun for the angle of the sun when compared to earth) or he could mess with sand to create glass for the humans, he could also have among  conflicts created the sterotypical issues between cats and dogs.

These suggestions were something I came up with in less then 10 minutes.