I'm sorry but I think Brave wins on this at least for now. In fact, with Brave you dont even have to install UBO, has tor built in, and its own torrent client built in, as well as no tracking features enabled by default. You don't have to install anything. It's all built in.
I tried using firefox, yet it was slow as fuck and often got stuck with being stuck with 'Performing a TLS Handshake' bullshit which apparently is a very known issue that's never been fixed. It's one of those cases with a billion fixes available for it, none of which actually work for most people.