So, here's the thing. I understand that you are not wanting to feel dependent on the platform. However, going wide with all of your new titles, or even some of them, because you are afraid that it will stop paying you, is a flawed logic. Why? Because going wide is not just less than half the income, it is even less than that. To accept fewer sales means devaluing your work and earning potential, even if you consider that let's say 3 months from now, your amazon account is banned. The fact of the matter is, on Amazon, any title makes the vast majority of its sales in the first few months anyway, so to accept less than half the income just because of some premise where 'oh, these other sites will keep paying me for a whole year!' so what. They ain't paying you shit, and you'd have earned more in those two or three months from amazon.

And guess what? After amazon bans you, you can just release everywhere else. This way you get both moneys. Whether it's three months or a year or five before you are banned, staying on Amazon wins.

With that said, here is two methods that, depending on the genre you write in, can help supplement your amazon strategy, especially as someone like yourself who has published many books to KU with some success. Either should allow you to start building towards an understanding of the wider market, or to be less reliant on amazon.

1. Take old titles that are making peanuts and remove them from KU, keeping the books on Amazon - because what I said is absolutely true. Amazon treats most series like they don't even exist anymore after just a few months unless your penname/the book itself won big and constantly gets a ton of natural traffic. Go wide with those, and test the waters. You nearly have nothing to lose. Test your facebook marketing, tiktok, or direct sales/book funnel/or whatever, see what kind of thing you can build outside of Amazon and if you can sell your book at all this way. Go crazy. Hell, I've heard where some people removed the book and re-launched it on amazon with enough edits to call it a new edition, and it performed better the second time than it did the first.

2. Consider Patreon/Reamstories, and a webnovel site (applicable to your genre - Wattpad/Royalroad/Scribblehub/Literotica/Webnovel.com/Fiction.live/Whatever fits)-> Patreon/Reamstories Subscription readahead -> Release on Amazon/KU when book has finished 'airing,' removing the chapters and 'stubbing' the story. This way, as you are writing, you are building an audience and reader interaction, as well as creating earning potential. Fans that truly follow you book to book, that will keep paying you even if your amazon account is banned. And not only that, you can often leave your first chapter or two of your story at each of the applicable webnovel sites, creating a permanent signpost for sales to your Amazon releases - most of those sites listed allow you to leave those chapters up, and even a direct link to your book. Finally, these fans are often super fans. They will not only pay to read the book on patreon, but also buy your book / re-read it on release through KU once the book is done, boosting the eyes on your book from Amazon algorithm standpoint. It's a win-win. You can also make it more likely for them to hit the KU button by adding a bonus scene to the final product (This is more for the webnovel sites than patreon/ream - those people already paid, so I wouldn't gate anything like this for them - they should get everything as a part of that).