In my opinion, the results have been very positive for the most part. The 2.5 free downvotes have been an absolute game-changer. I haven't personally seen that much more manual curation by large accounts but it's too early to tell. Perhaps that's because there aren't too many large accounts to begin with. But I've seen @blocktrades put a few good posts to Trending by giving them a massive vote. Also, Trending seems to be populated by many ThreeSpeak posts upvoted by accounts controlled by ThreeSpeak. That's all very positive.
What I believe is that powerful app accounts actually tend to be among the best curators because their incentives are perfectly aligned with what the company owning the app is trying to achieve - provided that the app itself has a sound long-term business case of providing goods or services consumers are willing to pay fiat for.