The best non-SystemD distro, in my eyes, is Gentoo. I tried to install it the other day, got almost finished, then had to leave and lost all my progress. I will say, its a process.
I use Alpine Linux mainly because its so nice and so much simpler than Gentoo is. I use Alpine Linux Edge (so I get the most up to date stuff), and I have had no issues with things breaking, but not having SystemD makes some things work a little different or a little harder to set up.