As for hosting, i personally use the free tier of Azure to host mine (https://azure.microsoft.com/en-us/products/app-service/stati...). It doesn't allow for anything "business related", but neither does Github.
It does however provide free SSL certificates, which is/was something that github pages didn't do at the time, but i think they've since changed that.
Zola is basically a stripped down Hugo. I don't see any reason choose it over hugo other than it's obligatory "written in rust" advantage.
I completely fail to see how implementation language would be an advantage to a static site generator, especially the security advantages that Rust is often recommended for. Memory safety is great if you're exposing a program, but here i'm just exposing the results of the static site generator, and none of Rusts features will be evident there.
The only advantage from my point of view would be site generation speed, which goes for both Go and Rust over Python/Ruby.