Here is a link to a post (and a link within to another post) regarding past discussions about time, if you want further references. Really, though, slower time lets you get more done in the villagers' short lifespans, and keeps the food from running out quite so quickly. Faster time allows the children to come of age faster, and once your village is fully established is probably the better so you don't feel like you're waiting for things in your village forever.