As previously stated, if you try to put limits on how much stake someone can use to vote than a whale will simply break his stake up into multiple accounts. If you try to say that you get 1 vote per account than fraudsters will make a zillion accounts with one nxt each. I think your judgment may be clouded by what you would like to be the case.
I have a solution that will allow almost complete fairness and can identify accounts being controlled by a singular user/group to change the result.
I think this a perfect time to use weak artificial intelligence algorithms.