I read several Gutenberg books every year and I've found the formatting to be mostly satisfactory. Not everything is precisely to my taste but it's just fine.
I'm an old guy and I read paperback books from the early days when they'd first become available in the 1950s. I began reading ebooks in the 1990s on an HP95lx. So that's about 40 years of reading paperbacks.
Paperbacks were always cheaper in the early days than hardbacks and they were less carefully formatted. Some were very nicely done. Many were not but I read them anyway and I rarely even noticed. There was no choice so why worry about it!
Well all that's changed. Now we have the magic of ereaders and computers with software that can perfect (or ruin) the formatting of any book. And that makes possible people who, on finding the slightest imperfection declare a book to be garbage!
Well folks, we're taught not to judge a book by it's cover and I don't think it's any wiser (or cooler) to judge a book by it's formatting. Those who do are not gurus. They're just fussy people.
I love to read and I judge a book by it's story and it's characters and the quality of it's writing. I'm happy if it's also formatted to my taste but that's not really all that important and more often than not I don't even notice.
By the way, the first decade of ebooks that I read were plain text files with no formatting at all beyond word wrap and paragraph breaks. They had a single font with no bold or italics and no right alignment. All that stuff came later. And they kept getting more and more popular. Imagine that!
Barry