Github pages is fine, but the extra gh-pages branch is kind of annoying. It's fairly clear (for obvious reasons) that they mainly think about Jekyll users, though I had a Hugo blog there for a while.
Netlify sounds great, but in practice I ran into an annoying issue that I couldn't resolve where I had to rerun every automatic build. This probably isn't really their fault but the forums didn't work.
Cloudflare Pages kind of just worked out of the box, and since I was already using it for my DNS, changing where the domain pointed took a few seconds.
I'd suspect, if you corrected for how many issues were particular to me, I'd say Cloudflare Pages ~ Netlify > Github Pages. I'm kind of surprised the latter charges you for custom domains; I do have to say there's more documentation for Github than any of the others.