I think this is the first time that this question has come up on the forum, which would suggest that most users find the available range of sounds to be sufficient. Click Track has been tweaked a few times over the years - It now works well and there are few forum questions about it, so I don’t see any need to replace it.
However, for the benefit of users like Brookshire that want a custom “click”, I have posted a new “Effect” plug-in that creates a click track from the selected audio. I have called the effect “Metronome looper” and it is available here: https://forum.audacityteam.org/t/metronome-looper/30680/1