I'm a fan of both Pandoc and LaTeX.
There's a pretty incredible amount of text preparation which can be done only in bog-standard Markdown, and if that's the case, go for it.
Markdown has its limitations, and if you find yourself starting to fight it ... consider that it's probably time to take the next step.
LaTeX itself is surprisingly easy to write, again most especially if you're writing simple documents.
And using Markdown to bootstrap creating a LaTeX document is also a good option. I find Markdown slightly lower-friction to write, and will use it when either composing or copying works initially. If they do require more complex formatting, I'll generate the first iteration of the LaTeX source with Pandoc, then dive into that and add additional elements or tweak complex sections as needed.
I think this is really the best of both worlds, because you can produce documents that (fairly) easily generate print books via LaTeX while simultaneously generating webpages or ePubs for electronic distribution.