The instant power down + burn fee could be optional. If you opt-in, you are sacrificing increased security for the ability to exit quickly.
Personally, if I had a second account that was whitelisted for me to withdraw to, an alt account (future could be a light account), for example, that would be fine for me. We can set it up so that anytime that whitelisted withdrawal address is changed, it takes a week before you can withdraw again. So even if my account was hacked, they could not instantly power down and send it to an exchange.
I'm not sure if we can have 2FA on withdrawals? If so, that would be another great feature to have, regardless of instant power down or not. Something like what ledger has, where you need to click ok on your physical device before the withdrawal goes through.
To be transparent, I feel these are changes I would like as an investor, and what other investors might like also. But, people do bring up good points to me how new people would want the instant power down, click on a scam link and get their account drained. And that would be terrible PR for Steem.
So I am not sold on the instant power down from an overall perspective. I do like to try and think of ways to get the cake and eat it too.