Q: if so, why? if not, what would be a better alternative?
A: sometimes i've wished it could be 10 days, but it's much harder for it to feel valid, because the rest of the world is so hooked on to the 7 day. All our devices tell us where we are in the 7 day. And adhering to that has a validity that you just can't get with another value. However, i do think it's good to rotate it and have the start time be different, so that way i feel like it's my own, and is also not subject to random monday holidays