FYI to any readers: Firebase Hosting has nothing to do with the other Firebase stuff. In fact, I personally dislike their live database quite a bit.
If you want to host a simple static site with HTTPS, Firebase Hosting really makes it incredibly easy. My only complaint is that they don't let you view access logs. Here's the official response [0] from the Firebase team as to why that's the case.
Once you have to do anything more complex I think it's better to use a different service. If you don't want to host anything yourself I've heard positive things about Zeit [1], although I haven't personally used it.
[0] https://stackoverflow.com/questions/29669725/can-i-access-w3...
[1] https://zeit.co/