I saw typst in my explorations but LaTeX had a few more of the controls I was looking for in print, and I really wanted a Standard Ebooks compliant EPUB. I might revisit at some time though. Thanks for bringing it up.
Last I checked, typst doesn't have baseline grid support (i.e., assures vertical lines of text across spreads are aligned, thus text doesn't bleed through recto to verso).
Also, I doubt if pandoc produces a highly compliant epub but it is always improving so who knows.