I did a video yesterday with some thoughts on the price and how the VEST to Steem Power ratio increases over time. As far as I understand, Steem Power now will get you more VESTs today than they ever will in the future. If you power down X Steem Power using today's ratio and then power up that same X Steem (maybe you purchased it again using bitcoin to avoid dilution), you'll end up with fewer VESTs than you would today because the conversion ratio is changing. You get diluted either way. Powering up now makes the most sense if you think powering up in the future may be a good idea, unless you think the price will drop faster than the dilution rate.

Obviously this is not investment advice, just my thoughts.