Instead of whales needing to remove their vote once a post hits the trending section, maybe for every X number of steem power you should get some sort of vote that boosts popularity but not dollar amount. Removing the need to go back and remove a vote.
I also think it would be interesting if we could choose to upvote more than once. It would use the same amount of voting power for each vote, but I think it would be an interesting topic to discuss.