It’s a trade off. “Free services” typically require more leg work and can come with legal or security risks. I used to have a great XBMC & torrenting setup years ago. I spent significant time customizing it and various plugins, extending scripts etc. I had fun, and took necessary precautions. Millions wouldn’t. Some are happy to pay €9/month to another evil corp for convenience (where it works for them).
NFSv3 (udp, stateless) was always as reliable as the network infra under Linux, I found. NFSv4 made things a bit more complicated.
You don’t want any NAT / stateful connection tracking in the network path (anything that could hiccup and forget), and wired connections only for permanent storage mounts, of course.