You're mostly right here, but at the end of the day I don't think it matters. Staking didn't stop the Sun takeover, and median values are exceptionally unlikely to be ideal values. The moving average here is done to give the most number of people the ability to vote, as a system that calculates median values would need to store and calculate all accounts votes at every vote, which won't scale. What seems like a median on Hive really is the median of 20 accounts who have a few key votes, a barely decentralized plutocracy.
The number of people who have left Hive is just shy of all them. Let's not stretch our imagination too much and think 90% of accounts hold 20% of the stake. On Hive there is nothing they could do even together to get a single witness voted from outside the top. At least with this system they could exercise 20% of the vote toward governance. The top 20 in this paradigm are the people who vote for all the apathetic accounts... which would have prevented the Sun takeover. It also disallows the biggest accounts from exercising more than 5%(hopefully closer to 2.5% with 50% apathy) votes as well, which addresses the last point: Any single vote won't effect a variable more than 5% in the arbitrary range.
The code does have vote range limits, so a negative vote will just be counted as a minimum. At this stage at least most of the range limits are fairly natural. Interest rates can't be negative, key holders are limited by Hive code, power-down voting range is something like 1 to 100 days... (which translates to 4 to 400 days for a full powerdown). The flip side is the 13 week power down on Hive is almost kinda voted on when there is a hardfork... but as much as people want it to drop in line with the rest of the market, there isn't even a path to do so.
To sum
Pros:
- Scalable
- Non-exclusionary
- Same or better whale influence limit as Hive.
- Same of better arbitrary vote range limits as Hive
Cons:
- Less plutocratic(?)