The AUR is pretty awesome. If a piece of software exists on Linux, it’s in the AUR. Even software that doesn’t have a native Linux version can sometimes be found these, e.g. repackaged versions of Electron apps for Windows.
And once you start really customizing your system, you’ll see the value of the Arch Wiki. If there’s something you can do on Arch, the Wiki probably has a well-written guide for it.