Sir Emi, as someone who no longer has ANY selfish interest in this game, please listen to me. Since I no longer have an account or any way to profit/benefit from this game, believe me when I say that I'm posting on these forums for the benefit of HP, its players, and you. The only reason I'm still here is because I want this game to succeed!
The issue is here is not that people don't like your updates; it's not even that you're implementing rounds, even though you said you wouldn't - it's that no one here feels that you're actually listening to them. I'm sure you read our posts, but you never really respond to them... You only post more information about the updates you've already decided to do. It happened to me countless times while I was playing and I see it happening again to the people who are playing.
Rounds are a good thing... they're a very, very good thing because, as you said, it allows massive updates and puts everyone on equal footing again. But, have you considered that they players here may not WANT to be on equal footing? Even low players (the thoughtful ones, anyways) don't want rounds or updates that are to the disadvantage of the more powerful players. Why? Because they someday hope to BE those powerful players, and they know that the result of them attaining their goals and becoming more powerful is that someday your updates will hurt them, instead of those who used to be at the top.
Here's my unbiased suggestion, made because I want this game to succeed - take it or leave it: Keep the persistent world we have now. Eventually, it will become so unbalanced that players will either ask for rounds, or the playerbase will be big enough that you'll be able to add another world with rounds. I'm sure that if players FEEL they're being listened to (I emphasize feel because it's more important how people feel about a game than the reality of it. I do think you're listening now, players just don't feel that you are), then donations will increase and the game will grow even faster. I'd like to use myself as an example, if I may... In the first week of playing this game, I looked around the forum and it seemed that you were a developer that listened to the community. In that first week, I bought gold membership and told at least a dozen people about this game, several of them started playing. In the days/weeks that followed, I began to feel that you either didn't hear me, or didn't care about what I was saying. I didn't donate another penny and I haven't told another person about this game since. I'm sure I'm not the only one who is in this boat either.
I graduated with a Business major a few years ago. Please allow me to share one of the (few) things I learned

Your job in business is not to make the best or the most balanced game. Your job in business is to please your customers and keep them interested in your product. Most, if not all, of the changes you've made could still have been made if you listened to us... it just would have meant they were made a little later and the people here would have felt valued because they were heard. The AP system needed balancing (and still does, imo) after it was released and caused quite a stir here. Imagine how much better it would have been if we'd all had input... we'd probably still have an AP system, but it would be much more balanced and we'd actually WANT it because we were a part of making it.
I (always) have more I could say, but this post has grown quite long. Please consider my words Sir Emi, because I really do have your best interests in mind. Peace.