I’ve continued tinkering with this, and added a new feature that helps with my use cases – you can now filter out specific artists from your random results.
There’s now a filter button in the upper right hand corner, I think it’s pretty self explanatory. I am finding it useful for avoiding artists where I might have a ton of records (such as Grateful Dead) showing up all the time in the random results.
You can of course enter multiple artists, and then clear some or all of them.
All info at GitHub, including updated documentation.