I actually think the best solution would be 1 vote per account but you can choose the percentage you would like to use per vote, meaning you could vote on one witness with 100% of your stake, or 4 witnesses with 25% etc etc etc.
I just assumed changing from 30 to 5 witnesses votes would be an easier (and quicker?) code change.
Yes thats a solution much quicker to implement, easier to code and probably also easier to outwit, instead of having one or a few accounts to manipulate the voting system you'll need some more with the same result, the DPOS broken.
My suggestion is to implement that change in the vote power (only for the election of the witnesses) because that way, you can't simply stake a lot of money creating some accounts but you'll need to have old accounts (so you will need some more time to manipulate the system allowing a reaction also) and with reputation, this way you'll add difficulty to the manipulation.
The change from 20 votes to 2, 10 or whatever amount you want only changes the number of accounts staked to allow that manipulation.
At least is my understanding of the problem, I could be wrong in this, if there is someone that can explain me how the change of number of votes for witnesses hardens the posible manipulation, I invite him to do so.
Well is what it does is require the amount of stake to control all the top 20 witnesses to be significantly more than it currently is. Had witness votes even been 10 instead of 30, what we saw on STEEM never would have happened...
Ok ty for the explanation. I thought that the stake needed was the same, just in more accounts. 👍