I wouldn't change the power down time. First, ask why we have powerdown times?

1. The first is to prevent stupid leverage games with vote power. Since vote power takes five days to recharge, you don't want powerdown time lower than five days.
2. To encourage people to hold and use stake.
3. To provide price stability via slowing the flow from staked to liquid

I think 13 weeks is a good number. It prevents people from including HP in their emergency fund calculations, while still giving reasonable access to their funds. It causes people to take to time to consider their commitment to hive before powering up and powering down. We want people to form long-term connections on hive, not treat it like a short-term transactional farm. So, yeah, keep the 13 weeks.