I use Firefox, but I'm disappointed.

If only there were more than 2 options for browsers...

You have Firefox and everything Chromium based, which is still Chrome as I understand it.

Not quite true, there are also the WebKit-based browsers: Safari, and some obscure ones such as GNOME Web.

Safari requires MacOS and thus isn't a replacement unless you exclusively use Macs. Also, for all its supposed support of privacy features it doesn't allow you to use good ad blocking plugins like uBlock Origin. I only use the thing because it's the best for battery life, otherwise I think it's significantly inferior to both Chromium and Firefox.

Aside from the other alternative listed below, even within the Chromium universe you have options like Brave and LibreWolf which are very privacy oriented - https://privacytests.org/