The SPS proposal to shorten the length of time of power-down from 13 weeks to 4 weeks is a good reason to power-up especially now that steem is very undervalued because you will get your money in a short time anyway if you decided to power-down. Whales anyway knows that if they sell anyway their big amount of steem they would crash the market so they will just sell it in increments, at least that is my opinion over that matter.
Regarding the the four-week power-down, they had done it in steem tribes indicating that a four-week power-down is a good idea for investors for a speedy recovery of funds which will in my opinion speed-up the steem economy as the money would flow faster.
I had been power-upping most of the time because I want to contribute to the "scarcity" effort to steem to make it more valuable if really everyone would try to hold it which would be better for something that would be made rare then it will appreciate in price. That is the idea of telling others to hold steem because it has a good effect on steem's price/value.
Now holding large amounts of steem or just some that you can earn will do you good when the price of steem would reach even a dollar then you would be glad that you collected like from these few months the steem's value had depreciated due to some external factors like the issues concerning BTC.
There are many benefits of having steem power, you can curate better with better returns especially if you have a large stake. People will also come to notice you because of course "You Got The Power" to do many things or good things to support the people, groups, steem tribes, or organizations in steem platform.
Also a bull run for BTC will influence steem as it was proven time and time again based on the chart because we just have to accept that most altcoins are just riding the coattails of BTC regarding Altcoin prices. So If you are bullish on BTC you will be also bullish on steem most particularly.