So, circling back on this, I did some more research, tried a bunch of apps and the most recent versions (some of the ones I tried were 2 or 3 years ago, which in device development that is like 10 years).

Here are all the ones I can find, including the ones @jackie_w listed, that will respect the published CSS of complex layouts on the first try, without any messing with settings, and also have some kind of synchronized note-taking system that lets you capture and export notes, and sync across devices:

* Kindle app
* Google play
* Kobo app
* Bookari app
* Pocketbook app
* FB Reader

This one was a surprise. I had tried this as recently as last year, and at that time it still didn't work. FB Reader is *really* coming on strong. They not only render all my complex books perfectly, they also do a great job of rendering footnotes, and give you settings to control that. They have a web-based sync where you can see and edit the metadata of your FB reader books, and they have a note-capturing system that syncs to Google Drive so you can retain control of your books and your notes. Interestingly, they've added cross-platform support so you can now run FB Reader on ios as well as android. In their roadmap, they play to add support for mac/linux/windows, so they are truly going for the universal solution.